Two and a half years ago. I tried to convince my surgeon to do them both at the same time. No go. I started doing the rehab I was taught on my fixed shoulder on my unfixed shoulder. I also ice it every night after I do bench and upper back work.
It took a while, but my unfixed shoulder doesn't bother me at all now, so long as I do the prehab and icing. If I skip it for too long, it starts to bother me.