On Thursday 18th June I am having a trip down to London. I am planning on getting the 08:21 London Midland Service from Coventry and getting an off-peak travel card for £28.30 as this is the first service its valid on. What do I need to ask for at the tickets office to get this ticket, an off-peak travel card to London? When coming back would I be valid doing Kensington Olympia to Watford Junc then a London Midland service back to Coventry or would I have to go to Euston first?