Hi once again,
when I make an A to B trip, using Google Pay, what sometimes happens is that I can’t touch in/out as I haven’t caught mobile signal.
This might be a problem for two reasons
1) maximum fare (however, it looks like there’s some AI behind the scenes, which completes incomplete journeys on the principle of commuting between two places)
2) potential revenue inspection
The only 100% solution then seems to be using standard Contactless/Oyster.