I remember the switch TO 12 hour shifts....basically, it was just 'do it'.... I had also moved to a different facility at the time, so was going into a new place- probably easier to get used to it that way since I didn't know what the 8 hour shifts were like there....just the weekend 7p-7a 12s (Baylor plan). Then Monday - Friday off
There are pluses with 8 hour shifts...you actually get some rest, and have time to get some errands done. I didn't like 3-11 since I don't go to sleep right away when I got home, and by the time I got to bed, slept, by the time I woke up it was time to go to work. Days and nights were essentially interchangeable re: what time I had off.... evenings were mine.
When I got tired of the 12s, I moved to a different town, and did 8s again; got tired of 8s, went to work 12s.... I was fortunate.
There are pros/cons to both...