As management and the RMT have failed to come to an agreement over pay, there’s a strike on the Heathrow Express and Heathrow Connect routes over today and tomorrow.
Heathrow Express is on a limited daytime and evening timetable
Heathrow Connect is suspended. Use First Great Western services instead
See http://www.heathrowexpress.com/amendedtimetable
Otherwise, if you’re travelling outside the prescribed hours, take the tube or taxi.
Good luck if you’re affected. And be sure to send a letter of thanks to Bob Crowe General Secretary of the RMT for calling out his members to strike.