The first face-to-face course scheduled for London since Covid-19 is the new and updated Trampoline Helper course. This is for ages 13+ and allows candidates to coach in club, leisure centre and school settings under the direction of a Level 2 coach.
https://www.british-gymnastics.org/course/28453/trampoline-helper
The course is being held at Chessington Sports Centre, KT9 2JS. Chessington South train station is next door and is in TfL Zone 6.