I just recovering from a RC injury, and I'm not sure what routine to go to now. Am I considered a beginner again? Could I get beginner gains off a full-body split? Or should I just try a upper/lower or a 4 day split?

I'm stuck between:

full body
upper/lower or push/pull
4 day split (no arms day)
3 day split twice a week
5 day


Routines I've done in the past are:

full body
push/pull
5 day
and currently doing 3 day split twice a week