Mine was pre cycling, but I did a lot of muscle damage. I couldn't raise my arm to even with my shoulder for a few months. Then at 6 months I had surgery to open my AC joint back up.
In the MC world the pros will race 1 week post op. Of course they get paid and can afford the risk, but If you are OK with the risks or crashing then do what you want to do. Just riding isn't going to have a negative impact on the healing.
How many fragments? The more fragments the longer I'd wait. I only had 3.