Kyle, contact Interim Director Tim Gault at Greenville County (SC) EMS. They switched from 24-hour shifts to a 10-10-14-14-four off schedule. A few years later they went to straight 12's. (Straight days or straight nights). Their last change was the 12-12 rotation with some power shifts since the early 1990's.
The shift pattern was 2 on, 2 off, 3 on (F-Sa-Su), 2 off, 2 on 3 off (F-Sa-Su).
Mr. Gault's email contact can be found here:
I was involved in the 5-year transition of a large EMS agency from 24s to 12s, using the same schedule that Ben Waller developed.
There is good, solid research out there that shows that at the end of the 19th hour, cognitive and psychomotor performance is the same as a person with a blood alcohol of 0.08 - legally drunk. That is the hard-core justification. We found that when unit hour utilization (dispatch) reached 0.4 (10 dispatched calls in 24 hours), crews could not get an uninterrupted 5 hours of sleep. That became the point at which we converted to 12 hour shifts.
With the shift Ben describes, you get a three-day weekend every other week, and three days off in the middle on alternating weeks - and you get to sleep in your own bed and be with your family every night.
As far as maintaining annual salary, you re-calculate your hourly rates to maintain the same income.
The hard part is that instead of needing 6 people to staff, on an average 56 hour workweek, you need 8 people to staff on an average 42 hour workweek. That costs some more, but it is far more safe and healthy.