Today, I took TBE into central Londonium, just south of the river. Due to closed roads, I took it on a sightseeing tours, crossing Oxford Street about a million times, through Picadilly Circus and Traf Sq, past Downing Street and the Houses of Parliament.
TBE taken as exempt from ULEZ, and getting expenses back from work can always be "interesting". But boogered if I was going on a train.