In message .com,
TheOneKEA writes

You've got it _completely_ backwards - there's no tipping-out required
at all.

A driver at King's Cross n/b makes an announcement, then proceeds
towards signal J10, which has a lit No.4 feather. The train will
proceed straight ahead into the original C&SLR n/b tunnel, bypassing
the 1960s tunnel built to divert the n/b Northern to make space for
the Victoria Line tunnels. This tunnel leads to the original scissors
crossover cavern south of Euston, where the train uses a facing
crossover to switch to the s/b line and pull into the s/b platform at
Euston, where he stops and changes ends.

What's a No.4 feather when it's at home?

London Underground have Arbour Lights on signals - not feathers.
--
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