The first week post-surgery, when I did the pendulum exercises, the circles were only between 3 and 5 inches in diameter! As the first and second week progressed they got bigger and bigger. Post surgery ROM was not great! I really could not get my elbow out from my side, but for those 2 weeks was told to just work on pendulum and elbow and hand ROM. There was no question of trying to forcibly lift my arm out to the side or front.
Advancing to 4 weeks post-surgery (1 week after meeting PT) I was able to get arm up in front to 90 degrees. I achieved this by slowly working on the stretching and strengthening exercises. Yes, once or twice I felt a little pain later in the day, and felt afraid that I had gone too far. The next day, I would ease off if it was still sore, or advance a little if it had settled and was not sore. Usually my PT would give me a set of exercises and on Monday they would be really hard to do and a little sore. I would keep going very carefully and by Friday they would be easy and I would be ready for the next set.
By 5 weeks, external rotation ROM was nearly 100%. At 8 weeks, I was using stronger resistance bands, but had not yet achieved more than 90 degrees up.
The hardest thing to get back was internal rotation, but as people on this forum, and my pt convinced me, this would come later with more stretching and work. I would say that now at approx 17 weeks it is at 95%.