I thought it might be worth updating on this.
I started using BPC 2.5 weeks ago; I really rolled the dice on this, as I don't know if this is going to cause any excess scar tissue build up. Rehabbed aggressively alongside it though, lots of ROM exercises, and one leg stability movements, I sometimes sit in front of the TV and rehab for 1+ hour.
I'm a little over 6 weeks post injury. I have full extension of my knee, and about 90% flexion back.
I'm able to walk normally, run up stairs, and pretty much do everything I was able to normally. Lightly jogged a mile a couple days ago with no issues. Have started squatting lightly again, bulgarian split squats, stiff deads.
The only painful part is the meniscus (which is macerated laterally). The last 10 degrees of flexion where you heel comes close to your ass is what's tight and hurts. Also got these 2 fun baker's cysts behind my knee that stick out if I over do it with activity, and can be a bit painful.
I don't think I'd progress this fast with recovery if I wasn't using BPC, it made a dramatic difference. My leg was stuck at an angle for 4 days, and I was on crutches for almost 2 weeks, so very thankful right now.
With that being said, I think it's best to not mess with this stuff post op, I'm in a situation where I can't get surgery until later this year, and even then it's going to be a decision based upon limitations in activity (when I start doing BJJ again).