Are there any sort of guidelines on how long pullback lasts or is it entirely dependent on the individual?
I think it depends on the individual, the overall health of the relationship, and whether or not there are any significant outside influences. In a healthy marriage? Maybe only a day or two. In wounded relationships, or if anything else is pulling them away? Could easily be longer.
Don't pursue, don't smother . . . but call him out if he is downright sh*tty with you -- cr*p behavior is cr*p behavior.