Returning to a failed ride

I prefer uneventful rides. Depending on how I feel, I choose rides that are just within, or just at the limits of, my perceived capabilities. Back in May 2022 I entered the Audax Dinton 100 starting from Dinton Pastures, just outside Reading. I decided to ride this as an ECE - extended calendar event - riding about 50 km from home to the start and 50 km back home afterwards. About 45 km from home I shipped the chain changing up from the small chain ring; it became completely stuck between the small chain ring and the frame and I had to abandon.