Roland Perry wrote:

In my book the absence of the Northern Line City branch is more
surprising.
I know the City is still pretty dead outside office hours, but Old
Street
and London Bridge?

Perhaps because of the looming rebuilding of Bank station, with a new
southbound platform tunnel for the Northern line?

That wouldn't stop them running northbound service via Bank and two-way
service via Charing Cross, would it?

Assuming they can cut the power off the two tracks independently. But they
probably need the northbound track for engineering trains to service the
works happening on the southern tracks

They've certainly run a one-way service in the past during prolonged
engineering works and I think it was around that time that they put in a new
platform at London Bridge. However the equivalent on the Charing Cross
branch was to instead blockade Charing Cross to Kennington.

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