They did say severe delays on the District Line in both directions.
However checked the TFL Service status app, which said problems to Richmond and Ealing Broadway, so no issues on Wimbledon stretch, I waited 2 minutes for a tube to Southfields.
Not the full picture from Chelsea
A24/Chessington/A3/Chelsea not sure how many pick ups you are making, but hitting early London rush hour traffic will probably mean 3 hours on the coach so about 6pm. But there is no certainty in this, just my prediction
Don't forget last season there was no public transport hence the issues getting away from the group. Hopefully with a full public transport service it should be quicker than last year for those going by coach