I had the patella graft done almost 20 years ago now. Just had a meniscus tear repaired a year ago but otherwise haven't had any real issues. I ran the Boston Marathon in 2000 and my knee didn't hurt any more than any other part of my body did afterwards
The rehab is the key. You sound like you are pretty committed to your martial art. Stick to the rehab protocol and don't rush things too much and you should be back to full strength by the end of the year at the latest.
Then you'll need more time to get over the mental aspect of the injury like not favoring the knee, but that's just part of the process.
Primal since August 2012. CW: 317.
I worked my a** off in rehab and within six months, I was doing everything I had been doing before. At that point in time, I was mostly running ultramarathons and skiing. I ran a trail 50 miler just before the six month point after the surgery and I was skiing without a brace two weeks later.
I've skied well over 500 days since the surgery, I ran more than 20,000 miles after the surgery before essentially retiring from serious running in the past couple years. These days, I mostly do CrossFit, lift heavy on my own, sprint, ski, ride my bike on occasion, and do some hiking. I never even think about the knee.
I was able to play tennis about 5 months after the surgery, which was amazing to me but also probably what led to the lingering problems with my menisci
I was in the identical situation 4 years ago. I blew my ACL 3 days before testing for my senior red belt rank in TkD.
The doctor went with a hamstring graft and while painful, it seems to have worked well for me. There were a couple of things that I believe helped wit the healing: recirculating cold water compress and electrical stimulation during rehab. I had little swelling and was able to get working on rehab sooner.
8 months seems a bit short for healing, as the bone needs to regrow around the graft. Sooner than that, you run the risk of it fraying. Take your time! As to sparring: you'll have to spar with a brace to prevent another hyperextension. Mine is a Breg like the NFL players wear and in slows reaction time and flexibility.
All that being said, I just tested in December for my senior second degree rank....so you'll eventually get there. Best of luck with your healing.