I barely could get past 90 to 95 degrees ROM, and without horrible pain, until over 6 weeks out. Now, when I look back, I know it was because I was just still too swollen. Then I started doing gentle movements on a stationary bike. Just backwards with a stretch, then forward with a stretch. Not going the whole way around. After a week (doing only 2 PT sessions a week), suddenly my leg went backward when it was warmed up. Then I did about 10 backward movements, pushing it to do so, but over a full 10 minutes, just doing the gentle stretch. After 2 more PT sessions, and being able to do a few more backward movements, suddenly I went forward. After 2 weeks of this, I could finally do a few minutes backwards and forwards.
As the swelling decreased, I was able to do a full 10 minutes actually cycling. Within a month, with more swelling decreasing, I could lower the bicycle seat and I got more ROM naturally.
By 4 months, I could bicycle steadily 15 minutes with the seat down 4 notches. And my ROM was within 5 degrees of my unoperated leg. Almost back to my butt standing up.
Next knee I will know not to hurt myself or let one of the PTs bully me because the ROM will come when the swelling goes down. I will try and stretch even when it is swollen, but excruciating pain gets you no where. When the knee is ready, it will move.