"Walter Briscoe" wrote

There is a Metropolitan Line closu Saturday 15 and Sunday 16 January,
no service between Moorgate and Aldgate. cf.
http://www.tfl.gov.uk/tfl/livetravelnews/realtime/track.aspx?offset=weekend
It does not appear on the posters displayed at Underground stations.
Yesterday, I flagged it on the LU CSC number 0845 330 9880, option 3.
A couple of hours later, I was told it was known and a decision not to
correct it had been taken.

Perhaps it's because Hammersmith & City trains are diverted to Aldgate,
which can't easily be shown on the posters as Aldgate is 'off-route' for
those trains.