Mohammed. I agree get a good dealer check it over. When I had my 1200 bonnie it had the same faults. I took it to Bulldog Triumph a local trusted dealer to me. It took them a few days and it turned out to be a loose connection. Ride Safe Joe
Keep rear brake on next time or place block of wood under rear tyre as a wedge to stop wheel from rotating. I think you'll find the message will not appear, agree with previous, conflict of readings between front & rear wheel speed sensors
OCTC actually means Optimized Cornering Traction Control. I'm currently troubleshooting this problem on my 900 Rally Pro.
You are correct. According to my Triumph Owner's Manual, this stands for Optimized Cornering Traction Control.