@rbmartin, just wondering: why would an Overground train have to run fast from New Cross Gate to Crystal Palace “because one of the cameras isn’t working”?
I’m sure there’s a perfectly good reason - but what?
Thanks!
@AndyS I don’t know, one of our members is a train driver for London Overground who may be able to help you with that answer.
@Joey_H is your man!
Now how can I become very cross with such a good explanation. 
Apologies. I thought it was you! Failed to do my research before posting.
In other words, “Have you tried turning it off and on again?” Universal answer these days.
Thank you for the detailed explanation, @Joey_H. It never occurred to me about nearside and offside cameras!
Any other night a flying visit to Norwood Junction would have been most welcome. Fortunately I read the display in time to “de-train”. (Is that the correct word these days for ‘Get off’?)