I have a soon-to-expire Heathrow Express ticket that was purchased for travel from Heathrow to Paddington and back. It was used for the Heathrow-Paddington "outward" journey, but I didn't use the return and won't be using the train to go back out to Heathrow again anytime soon. However, I will have another opportunity to travel from Heathrow to Paddington again very soon. Has anyone ever used a return HEX ticket to travel the same direction twice? I know that wouldn't work on National Rail, but I get the impression they might not care/notice on Heathrow Express?