Whatever the change, you can bet your bottom dollar that the ops managers have already formulated the new crew/shift makeup they want, any talk of "engagement" with the workers is just lip service.
At the end of the day though, any change to the roster means a vote, and we know how hard it is to get a yes vote if there is any shadow of doubt.
I wouldn't fancy permanent "A" checks or going back to the old 8hr night shift.