Don't know if this is the right place to post these but here goes. Just seen this on facebook.
Anyone travelling by train to the Palace game & were going to travel between Watford Junction (WFJ) - Thornton Heath (TTH) via Clapham Junction (CLJ) on the Southern rail service, DON'T as there is no service between between WFJ - CLJ. You are advised to travel to Euston, tube to Victoria, then Victoria to TTH.