Five weeks
When I turned in my resignation at the first of April, my boss asked me to give him five weeks to fix things. This was because five weeks was the projected amount of time before we moved to the new center. Now I'm no fool so I didn't believe for a moment that we would move on time or that the move was going to fix anything, but I didn't have another job lined up so I figured, why not? Well, we did eventually move seven weeks later, but just as I expected, the move didn't fix things. We are now trying a five week rotation that has me working over twice as many evening shifts with a weekend off only once during those five weeks. Now there are *some* improvements to this schedule because I won't be flipping between days and nights in the same week (which was killing me), but will work one week of all days shifts and then one week of all night shifts. I'll also have two days off in a row for the most part (just not on the weekends.) And one weekend off every five weeks beats the heck out of one weekend every three months. There's also the fact that I'm on vacation during one week of this rotation and it lands conveniently during one of the night shift weeks. Plus, who knows? Despite my misgivings, it might work out fine and I'll actually like this schedule (not likely, but stranger things have happened.)

I don't see this as doable over the long haul, but what's another five weeks? It will pass in the blink of an eye and I can always evaluate the situation again at the end of it.