Target specific muscle days

Hello all, been going to the gym since late February. Been doing quite well. I try to do one day of upper body and one day of legs. Unfortunately, I was diagnosed with an abdominal hernia and my physical therapist has got me on working out only one ab muscles and forbids me from workout any other core muscles. I find my upper body days are a too long. I wish to shorten them up while at the same time going to the gym more often.

I was thinking of having one day dedicated one group like a day for chest, a day for lat or a day of delts. This seems like a lot of days so I was thinking I should group them by the muscle and the agonist muscle. bicep and triceps are going to be used on all those days anyways so no need to dedicate a day for them. I am worried of burning out.

Do any of you have any advice.