You have to set the time to 11:59pm on the date it is NOW. Then , when it turns 12am (midnight) Set the time again to what ever time they're awake. Hope this helps. It will (should) work.
I don't like this version >.> It's not really 'new' either. After playing it for a while , I find it to be boring >_<;; Sorry to burst your bubble but . . . ((((POP))) XD