Coaches can give a better answer, but I find myself in almost the exactly same situation.
Two weeks after a minor surgery and “finally” off antibiotics I resumed training. Lost fitness of course, and surprisingly lost some weight and body fat, I resumed training. I chose to do the Walk/Run workouts a couple of days for the transition, and it seems to have worked.
I don’t plan to return to my original race schedule, but I am ready to rebuild with some endurance workouts next week. Instead of my original 1/2 Marathon I have registered for a 10K two weeks later, in late April…