We, 2 adult will have a round trip by train between Oxford and London in Sept. Are you qualified by the 2for1 offered by National Rail? During our 7 days stay in London, how many times can I use the 2FOR1 discount? from the FAQs below, we need to have the terminal station close to the attraction? Obviously, our tickets only show 1 terminal and we will use tubes after we arrive London. Are we still eligible for the west minster abbey , town of London and St Paul in different days during our stay in London?
https://www.daysoutguide.co.uk/faqs
"All tickets should show that you have travelled to the attraction by train, whether that be ‘London Terminals’ for 2FOR1 London attractions, or the train station nearest to the attraction itself. Tickets that have a destination too far from the attractions location may be denied by attraction staff. Details of the attractions nearest station can be found on the attraction’s listing page."