You can't believe how many people search for the terms "12-hour shift schedule examples" or "24/7 shift schedule examples." They apparently assume that any attractive schedule example will work. They also believe that they can "sell" their co-workers or upper management on this new schedule.

These are dangerous assumptions. In groups of less than 50 employees, work patterns you find searching the Internet won't necessarily be the best choice. That's because they are designed for 24/7 coverage using 4 crews. They also may have different overtime weeks. And pushing a single scheduling option is rarely going to gain widespread support or buy-in.

When I design schedules, creating the work pattern is the very LAST STEP in the process. I start by asking how the workload varies by hour of the day and by day of the week. Most organizations don't track this, but they can tell you the coverage requirements at different times of the day. Usually this is expressed in 8-hour blocks because the organization was using 8-hour shifts and they know the coverage needed on each shift. In many cases, this approximates but doesn't accurately match the work volumes.

Many smaller organizations have either a heavier or a lighter workload on weekends. Police departments and dispatch units are often busiest on Friday and Saturday, especially in the evenings or when the bars close. Other industries often have less work on the weekends and can reduce the coverage to just one or two people all day Saturday and Sunday.

Once you know the coverage requirements, you can determine whether the available resources are adequate. The resources are the staff size, absence rate, and average hours of work each week. I use a staffing calculator similar to the one on my website. You can access it here: http://www.shift-schedule-design.com/Staffing_Calculator.

Then I decide which shift lengths would best match the coverage requirements. In most cases, this is either 8-hour or 12-hour shifts. 10-hour shifts are only considered if the workload increases for 6, 12 or 16 hours a day. That's because the 10-hour shifts overlap for that many hours, depending on how you use them. For most 24/7 organizations, 10-hour shifts just have too many limitations.

The next step is to look at the preferred schedule format, i.e. fixed or rotating shifts. Although employees tend to prefer fixed shifts, they present several challenges for management. With 8-hour shifts, using fixed shifts also may require a few more employees.

The final step is to develop different work patterns. Sometimes, popular patterns such as the Panama, Pittman, DuPont, 4-on-2-off, 6-on-3-off, etc. can be used. Sometimes these patterns can be tweaked to fit the organization's overtime week. Sometimes a pattern must be created from scratch. The key point is that you should never start with a pattern. It will not ensure the most effective or efficient use of your staff. It can cause over-staffing. It can cause unnecessary overtime or sacrifice the maximum possible number of weekends off. It should always be the last step in the design process.

During this final step, other considerations may come into play. For example, the group may be able to build relief coverage or training time into the schedule. They may have a bargained requirements for no less than 2 consecutive days off. Or they may want a slow shift rotation. These often require custom-designed patterns.

One last point. I always encourage clients to choose from multiple options. This allows you to compare the pros and cons, and make the necessary tradeoffs. I also recommend that clients use a strategic schedule selection process, as described here: http://www.shift-schedule-design.com/Schedule_Selection_Process. This will lead to superior choices that are supported by a majority of the employees who must work the schedule plus managers who oversee the operation.

Your group needs a new employee work schedule. Maybe the staff size has changed. Or the demand for your product/services requires you to increase the hours of operation. Perhaps you've run out of space and need to add a 2^nd or 3^rd shift. Maybe you're just tired of listening to employee complaints. Whatever the reason, you know that something has to be done.

If you're like most managers in this situation, you may be asking friends or associates in your industry about their schedules. And you're probably searching the Internet for additional ideas. It's important to find a solution that doesn't require a lot of time or money. Your regular responsibilities can't be put on hold and your budget has little room for unexpected expenditures.

Unfortunately, a schedule that's not tailored to the organization's hours of operation, coverage requirements, staff size, and pay week will rarely be a good solution. You will probably end up with problems such as these:

• Ineffective coverage
• Inconsistent coverage
• Over-staffing
• Unnecessary overtime
• Minimal weekends off

Let's look at each of these problems a little closer.

Ineffective Coverage
The fundamental purpose of the schedule is to ensure the right number of people at work during all the hours of operation, i.e., to match the coverage with the workload.

• If the work volume is fairly steady, then the coverage also should be constant. A schedule with hours of overlapping shifts would be ineffective for these situations. For example, using 10-hour shifts in an organization with a steady workload would be a waste. There is no need for the 6 hours of double coverage while the shifts overlap. It would also be costly, since it would require 25% more personnel than a schedule using 8-hour or 12-hour shifts.
  
  
• If the work volume varies by time of day or day of the week, the coverage should reflect that. Possible solutions include mixed shift lengths, overlay or power shifts, 10-hour shifts, staggered shift start times, or different coverage levels on each shift. An example of ineffective coverage is a police department with a heavier workload on Friday and Saturday evenings that uses a schedule with the same coverage throughout the week.
  
  

Inconsistent Coverage
An ideal schedule consistently matches the desired coverage. Some schedules don't do this. Here are two examples:

• Sometimes companies have more staff than the minimum necessary. They may have reached this position because they were using an inefficient schedule which required more employees or they thought the extra personnel would help to cover absences. A small food processing firm needs 5 people working on a 24/7 basis. They employ 23 people, three more than the minimum necessary. They could have used the extra employees to build relief coverage into the schedule, but instead adopted a schedule in which the coverage varies between 5 and 6 people.
  
  
• Sometimes organizations adopt schedules that produce fluctuating coverage because they like the work pattern even though it is a poor match for their requirements. For example, a warehouse needs at least 3 people working around the clock. They chose a schedule with a 6-on-3-off pattern because their employees thought it would be better than the current schedule. Because of their staff size, however, the coverage varied between 2 and 3 people. To maintain the minimum coverage levels, the company was forced to hire 3 more employees. The coverage now varies between 3 and 4 people. In this case, choosing the wrong schedule increased their costs by 25% and it is still producing inconsistent coverage.
  
  

Over-staffing
Nobody wants to overstaff, yet it happens all the time. It occurs primarily for three reasons:

• The organization sets an annual target of less than 2,080 work hours per employee (<40 hours a week). For example, a police department has a labor contract that limits employees to 1,820 hours a year. This is an average of 35 hours a week. They need 5-person coverage using 10-hour rotating shifts. Because of the reduced work hours, they have to employ 30 officers. If they worked an average of 42 hours a week, they would only need 25 officers.
  
  
• The organization builds extra coverage into the schedule rather than using relief coverage. For example, small utility needs 4-person coverage at all times. Although they could do this with 16 people working an average of 42 hours a week, they employ 20 people to have 5-person coverage at all times. They could have employed 17 people (rotating shifts) or 18 people (fixed shifts) and built relief coverage time into the schedule which would have accomplished the same thing.
  
  
• The organization wants a schedule with no built-in overtime. A small hospital needs 3 CNAs on a 24/7 basis. Their 8-hour fixed shift schedule requires at least 12 people working an average of 42 hours a week. However, they are instructed to eliminate overtime from the schedule. To maintain the same coverage, they are forced to employ 15 people at 40 hours a week.
  
  

Unnecessary Overtime
People adopt work patterns that were intended for a different pay week. If they don't tweak the schedule, they could end up with highly unbalanced work weeks and more overtime than necessary. Example:  A small trucking company found a schedule that was intended for a Sun-Sat pay week. Since their pay week starts on Monday, the employees work 60 hours one week and 24 hours the next, and the company has to pay for an extra 3 hours of overtime per employee every week.

Minimal Weekends Off
Employees want to get as many weekends off as possible. This may not be achieved if the organization chooses the wrong schedule or doesn't modify it to fit their pay week.

• A nursing home has a schedule with several split weekends in which employees work either Saturday or Sunday instead of both. A different pattern would have provided more full weekends off.
  
  
• Many work patterns work best for a certain pay week. For example, a popular 8-hour rotating shift schedule pattern that requires only 4 or 5 consecutive days of work provides 1 weekend off every four weeks - only if the pay week begins on Sunday. Trying to use this pattern with a Monday start will mean the workers never get a full weekend off.
  
  

Conclusions
When organizations select a schedule that is not matched to their specific resources or requirements, employees can suffer from fewer full weekends off and the organization can suffer from ineffective coverage and higher costs.

Sometimes an organization's scheduling requirements make it difficult to find a solution. Here an example from last week. This client operated on a 24/7 basis. It used to have 7 employees, but was just given authorization to hire an 8th person. They wanted 8-hour rotating shifts with no overtime in the schedule. The difficulty was the labor agreement that required employees to have 3 days off after any series of night shifts.

My first step was to determine what kind of coverage the 8 employees could produce without incurring any overtime. We discussed a couple of different possibilities and the client agreed on weekday coverage of 3 on days, 2 on afternoons, and 1 on nights. The weekend coverage would be 2 on days, 2 on afternoons and 1 on nights. This combination of variable coverage (shift-to-shift and weekday-to-weekend), no overtime, and 3 days off after the night shifts made the schedule design especially challenging.

My second step was to create a schedule primarily using 7 consecutive shifts. This is shown below:

The way this schedule works is that the 8 employees are initially assigned to different weeks of the schedule (A to Week 1, B to Week 2, and so on). After they complete the first week, they move down to the next week of the schedule. They continue doing this until they finish the 8th week of the schedule, after which they rotate up to Week 1. All 8 employees are working the same schedule; they are simply in different weeks of the 8-week cycle.

Although this achieved the desired coverage and had 4 days off after the night shifts ended in Week 4, there was one 48-hour work week and one 32-hour work week. My first thought was to simply move a shift from Week 2 to Week 8 to balance the hours. The only open days in Week 8 were Thu, Fri and Sat. Moving the Thu shift from Week 2 would leave an isolated workday (Wed) in that week. Moving the Fri or Sat shift would result in an isolated workday in Week 8. An isolated workday is one with days off both before and after it, which makes it vulnerable to excessive absences.

Obviously, my initial approach would not satisfy all of the requirements. There are no rules of thumb or proven procedures for doing what I did next. It's like trying to solve a puzzle by moving shifts around and experimenting with different approaches. Finally, I was able to come up with 5 options that worked. Here is one of them - just to show you that it can be done:

If you have multiple requirements like this client did, designing it by yourself will probably be too time-consuming or too frustrating. You might be tempted to accept inconsistent coverage or coverage that doesn't match your desired levels. But is it really worth those kinds of sacrifices, when you can hire a reasonably-priced expert to help?

Did you know that your shift schedule actually determines how the organization will use its two key labor resources: employees and overtime? Many people don't. They think the schedule simply determines when employees come to work and when they get time off. That's why they focus on specific work patterns (e.g., 5-on-2-off or the DuPont rotating shift pattern) or shift lengths (e.g., 10-hour shifts) when searching for a new schedule. As a result, they end up with schedules that have attractive patterns or a preferred shift length, but make poor use of the resources. Here are two examples.

Example 1

A group works 24/7. It needs 2-person coverage for 16 hours and 1-person coverage for the remaining 8 hours when the work volumes are lightest. They have 7 employees working 8-hour rotating shifts. One of the employees spends a weekend searching for free schedule examples on the Internet. He comes up with a 12-hour rotating shift pattern that provides every other weekend off. This pattern is sometimes called a Panama schedule. The other employees think it would be great to get that many weekends off, and whole-heartedly support the change. The problem is that the pattern uses 4 crews. Because of the group's size, it would have 3 crews of 2 people each and 1 crew with just one person. The coverage would fluctuate between 1 and 2 people on each shift. Adopting this pattern would create a complete mismatch between the coverage and the workload.

Example 2

A police department with 18 officers needs 4-person coverage on a 24/7 basis. They are working an 8-hour fixed shift schedule that follows a 4-on-2-off pattern. Due to budget cuts, the department will be losing 2 officers. They decide to keep the current work pattern because the officers are familiar with it and seem to like it. The problem is that the pattern only works properly with 6 people per shift. Using that same pattern with only 5 people per shift will cause the coverage to fluctuate between 3 and 4 people. The worst part is that the reduced coverage occurs on Wednesday through Saturday (when workloads are the heaviest). Once again, the chosen schedule is not an effective use of the department's resources.

You increase the likelihood of an inappropriate, ineffective, or costly solution if you ignore the resources and business requirements during the schedule search. We recommend the following process to make optimal use of your labor resources:

Step 1

Compare the staff size with the coverage requirements. Our free staffing calculators can help:  http://www.shift-schedule-design.com/Staffing_Calculator. If the desired coverage can be achieved with the existing staff, you can proceed to the next step. Otherwise, determine whether adding overtime to the schedule will allow you to consistently achieve the coverage requirements. If you're still short, you'll either need to hire more staff or reduce the coverage.

Step 2

Compare different shift lengths with the coverage requirements to identify the best fit. Our free schedule evaluation can point you in the right direction: http://www.shift-schedule-design.com/Free_Schedule_Evaluation. If the workload is steady throughout the day, you could use either 8-hour or 12-hour shifts. Anything else will have overlapping shifts and will require extra resources. Using 10-hour shifts, for example, would result in 6 hours of overlap (and double coverage) every day of the week. Plus it would require 25% more staff. That would be wasteful. What if the workload varies by hour of the day? For instance, if it changes at 8 hour intervals, using 12-hour shifts probably would not be a good match. In situations with highly variable workloads (e.g., communication centers or airline security operations), you may need to adopt multiple shift lengths with staggered start times. These situations often require professional assistance. 

Step 3

Find a work pattern that fits or can be adapted. In Example 1 above, the group's size (7 employees) does not match standard 4-crew patterns, so the schedule might have to be created from scratch. It might be possible to modify a standard 4-crew pattern, but this requires some experience in schedule design. In Example 2 above, the group's size (16 employees) would allow them to use any popular 4-crew pattern with 12-hour shifts. If they decide to stay on 8-hour fixed shifts, they would need to modify patterns that use 4 crews per shift.

Step 4

The last step of the process is to tweak the pattern to maximize the weekends off. At this point, it's important to take the overtime pay week into account. You don't want the changes to create unnecessary overtime or compromise the coverage. A professional schedule designer can help with this step.

Conclusion

Shift schedules determine how you will utilize your labor resources. If you want to make optimal use of these resources, we recommend a 4-step process. Yes, choosing a shift length and work pattern are steps in the process, but they are not the best places to start. If you don't feel comfortable following this process and want the best possible schedule, contact us today.

Catchy title, don't you think? Maybe I should write a book...

Anyway, I just finished adding a new page to the website with this same title. I don't want to repeat the article here, but I'll give you a little teaser from the article itself:

"If your group needs a new shift schedule, you naturally want to find the best possible schedule. But how do you know what's best? And how do you come with options for the group to consider? Let's start by exploring three things a good schedule must do: (1) optimize the coverage, (2) minimize the labor costs, and (3) maximize employee satisfaction."

Here's a link to the article:  http://www.shift-schedule-design.com/Shift_Schedule_Design_for_Dummies.

The article also lists a process for designing schedules, but it's the 3 things a good schedule must do that is most important. So many people think a good schedule merely has the shift length they want or an on-off work pattern they heard about (e.g., Panama, DuPont, or Southern Swing). They end up with schedules that produce ineffective or inconsistent coverage, cost more than necessary, and don't maximize weekends off for the employees.

I hope you've had a chance to try out our new staffing calculator. If not, here's a link:  http://www.shift-schedule-design.com/Staffing_Calculator. You can use this set of calculators for several purposes:

1. Staff size. You can see how many employees are required to achieve the basic coverage requirements. This does not factor in other considerations such as absences, maintenance, or training. But it will quickly tell you if you have enough staff.

2. Coverage. If you don't have enough staff for the required coverage, you can determine what coverage levels are possible. If you have more than enough staff, you can also determine how much coverage is possible.

3. Shift length. You can explore the staffing and coverage implications of different shift lengths. For example, suppose you want your group to adopt 10-hour shifts. You can use the calculator to determine whether they are feasible for your minimum coverage requirements. Alternatively, you can see how much coverage is possible for a given staff size.

4. Weekly hours. With 8 and 10-hour shifts, the calculators show the staffing requirements using 40 hours per week and 42 hours per week. The reason for the 42 hours is that many 24/7 schedules require this much time to avoid gaps in the coverage.

5. Schedule format. You can also see whether changing to fixed shifts is feasible for your group. Each shift length except 12s has separate calculators for fixed shifts and rotating shifts. The reason is that fixed shifts (with 8s and 10s) often require a few more staff than rotating shifts for the same shift lengths.

When organizations need a new shift schedule, their managers often begin by searching for either:

• A specific work pattern, e.g., Pitman, DuPont, 6-on-3-off, or 4-on-2-off
• A desired schedule format, e.g., 10 or 12-hour fixed shifts

This approach often will produce inferior results for three reasons:  (1) workload variations, (2) crew requirements, and (3) overlapping shifts. Let's take a look at each of these reasons in more detail.

Workload Variations
Most smaller organizations don't have a steady volume of work. Some have a workload that varies by time of day. For example, police and communications centers are often busier during the evening hours. Customer service centers may have more calls during the daylight hours, such as 4-person coverage from 0800 to 1700 and 2-person coverage from 1700 to 0800. Some organizations don't have a steady work volume throughout the week. For example, they may have lighter workloads on the weekends, such as 4-person coverage Monday to Friday and only 2-person coverage on Saturday and Sunday.

Most 24/7 schedule patterns are designed to provide the same coverage around-the-clock, e.g., 3-person coverage on a 24/7 basis. This are inappropriate for organizations whose workload varies by shift or day of the week. It's important to keep in mind that the primary reason for having a schedule is to match the coverage with the workload. Managers tend to forget this key point when they search for a schedule pattern they hope will improve morale or reduce turnover.

Crew Requirements
Work patterns are designed for a specific number of employees or crews. For example, the Pittman 12- hour shift pattern (also known as an Every Other Weekend Off schedule) is designed for 2 crews per shift. The 6-on-3-off pattern using 8-hour shifts is designed for 9 crews (or employees) on each shift.  Yet organizations use these patterns with the wrong number of crews all the time.

I just finished a job for a client that was using the 6-on-3-off pattern with only 5 employees on each shift. As a result, their coverage varied from day to day in a haphazard fashion. Employees liked the schedule pattern, but it was not an effective solution for the organization. Starting the search for a new schedule with a specific pattern in mind will rarely result in the most effective choice for the organization.

Overlapping Shifts
When organizations choose a desired shift length in an attempt to satisfy employees, they fail to consider the impact on coverage. This usually occurs with 10-hour shifts. Employees want to get an extra day off each week and they dread the idea of 12-hour shifts. So 10-hour shifts seem to be an ideal choice. The problem is that they come at a high price for the organization.

Since the organization is now working 30 hours a day (three 10-hour shifts), this requires 25% more personnel or 25% less coverage. For example, a group of 16 employees on 8-hour shifts had 4-person coverage around-the-clock. After changing to 10s, the coverage dropped to 3 people. In addition, there are six hours every day in which the shifts overlapped. They now had 6 people working for this six-hour period every day when they only needed 4 people.
 

Summary and Recommendations
Have you ever reflected on why you have a schedule? Yes, satisfying the employees is important. But that's not the reason for the schedule. The schedule is there to ensure the organization deploys its resources as effectively as possible. Many managers seem to forget this critical point. They hear about a popular pattern or they think 10-hour shifts will make everyone happy. They don't think about the impact on the organization.

I'm not saying that we ignore employee preferences. I'm simply saying that they're not the starting point in the search for a better schedule. Here is the approach I recommend:

1. Determine the hours of operation. Does the organization operate 24/7 or something less than that? If the hours are less than 24/7, make sure they are based on business requirements, not on shift length preferences. For example, a recent client was looking for 20/7 schedule. He didn't have enough staff to achieve the desired coverage levels, so I questioned him about the hours. He said he chose them in order to justify using two 10-hour shifts. He forgot that working an extra 4 hours a day would require 25% more personnel.
2. Determine whether the workload is constant or variable. If it's variable, two general approaches can be followed. One way is to establish base coverage using either 8-hour or 12-hour shifts and then add an overlay shift (sometimes called a Power shift) to boost coverage during the busy period. The other way is to combine different shift lengths or use 10-hour shifts and match the overlapping shifts with the busy period(s). 
3. Identify the coverage requirements (i.e. the number of employees you need to show up for work - by hour of the day and day of the week). Many managers mistakenly specify the coverage requirements using the current shift length. This simplifies the task, but it may not be the best match for the workload. If you can identify the work volumes and coverage requirements by hour of the day, that is ideal.
4. Decide which shift lengths are the best fit with the coverage requirements. If the workload is constant, 8-hour or 12-hour shifts would be best. If the workload varies, which shift length(s) are the best fit? If more than one shift length would work, which is preferred? Notice that shift length selection is the 4^th step in the process, not the first. 
5. Calculate whether the staff size is adequate to produce this coverage. If not, overtime may have to be built into the schedule or more employees hired. The free staffing calculator on my website can help with this step. Go to:  http://www.shift-schedule-design.com/Staffing_Calculator. If there is more staff than necessary, can these "extra" resources be used to build relief time into the schedule to cover absences?
6. If the resources are adequate, it's time to start the actual shift schedule design. Often you can apply common schedule patterns as a starting point, and modify them to fit your unique circumstances. Suppose you have 5 employees on a 12-hour day shift. This will require a 5-week schedule. You could start with a common 2-week pattern, double it to 4 weeks, and add a new pattern for the 5th week. An important consideration is to use a pattern that matches your organization's pay week. If the original pattern was intended for a different pay week, you could end up with unnecessary overtime and you could lose some of the weekends off. Again, please note that pattern selection is the 6th step in the process - not the first step.
7. We always try to create several different shift schedule options to show a range of possibilities, such as the number of consecutive days worked, different shift lengths, different work patterns, with or without relief coverage, and so on. The goal is to both satisfy client specifications and explore possibilities the client may not have considered.

The bottom line is that the search for a new schedule begins with the business requirements, not with employee preferences. If you reverse this by searching for a schedule that you think employees will be happier with, the organization will suffer the consequences. My recommended approach does not ignore employee preferences; it just doesn't start with them.

In my last 4 posts, I recommended evaluating potential schedules by using the following criteria:  (1) effectiveness, (2) efficiency, (3) sleep, and (4) employee satisfaction. This post will cover the fourth and final criterion - employee satisfaction.

Employee schedule preferences are largely driven by demographics (age, gender, parents with young children, single parents, students, etc.) and past experiences with different schedules. The best way to determine their preferences is to show them a broad set of approaches, such as: (a) higher staffing levels vs. built-in overtime, (b) different shift lengths, (c) fixed vs. rotating shifts, (d) fixed vs. rotating days of work, (e) relief coverage vs. more coverage, and (f) others. Once you have zeroed in on the “best” overall approach, you may want to drill down into specific options, i.e. examples of different on-off work patterns associated with the preferred approach.

Larger organizations can do this in a multi-step process. They can begin with a survey of the employees that identifies their lifestyle patterns and general preferences for different aspects of the schedule such as start times, overtime, rotating vs. fixed shifts, longer shifts vs. fewer days off, longer breaks vs. fewer consecutive work days, and so on. The next step would be to show them examples of different options that meet the business requirements and let them vote on the options they like best.

If you start out by asking employees if they want to change to a 12-hour shift schedule, most will say, "No way! I'm not working that many hours." But when they are questioned about the various tradeoffs required and then shown actual examples of what that means, they are better prepared to make a choice that satisfies most of the needs.

In my next post, I will show you how to combine all four criteria into a single evaluation survey.

In my last 3 posts, I recommended using the following criteria to ensure a comprehensive approach to the schedule selection process:  (1) effectiveness, (2) efficiency, (3) sleep, and (4) employee satisfaction. This post will cover the third criterion - sleep.

When a schedule adversely impacts employee sleep, this can lead to health and safety problems. The following schedule elements are known to do this:

1. Excessive hours of work. If the schedule averages more than 42 hours a week, this could be a problem Since additional overtime is often needed to cover absences, 42 hours is probably the most hours the schedule should have. There may be occasional need to increase the hours of work, but as long as it doesn't last more than 4 to 6 weeks, you should be okay. You can read more about this topic here:  http://www.shift-schedule-design.com/uploaded/files/Overtime%20Problems.pdf

2. Too many consecutive days of work. For 8-hour schedules, more than 7 consecutive shifts is excessive. For 10-hour shifts, more than 5 consecutive shifts is too many. For 12-hour shifts, more than 4 consecutive shifts is too many. There are a few 12-hour schedules that have an occasional block of 5 shifts in a row, but they tend to offer longer breaks to recover from the sleep loss on the days of work.

3. Rotating shifts. Employees who work fixed shifts tend to get more sleep. Employees assigned to a permanent night shift get about the same amount of sleep as employees on a rotating shift schedule. There are many good reasons for organizations to avoid fixed shifts, but management should be aware of the impact on employee sleep and alertness. To read more about this topic, check this out: http://www.shift-schedule-design.com/Fixed_Shifts.

4. Early start times. If the day shift starts before 7 a.m., employees will get less sleep. I wrote a blog post on this subject several months ago. Here's a link: http://www.shift-schedule-design.com/Blog?m8:post=problems-with-early-morning-start-times.