In message , Paul Corfield
writes
No of course it is not the tourist's problem - there should be adequate
information to make sure are aware of what ticket works where.

But this is what's missing. I've agreed to check Ealing Broadway station
tomorrow, and when I arrive at Paddington I'll have a look there as well
(and depending on whether or not I arrive on a platform *inside* the
underground barriers or not, try to find the Oyster validator - I'll be
arriving on a paper NR ticket and transferring to the H&C line).
--
Roland Perry