At about 19:30 on Friday (21st) I was waiting at Liverpool St for a Circle
Line train and 4 out of 5 trains shown on the board (before mine) were Met
trains to Aldgate (which presumably then had to turn around and travel
back).

I thought that the Aldgate bit only ran at rush hours and whilst I can see
that a last train at about 20:00 is reasonably still inside the "travel home
from the city" work hours, I can't believe that it has a two minute
frequency at that time of day.

Was there something special about the service on Friday, or is this a normal
service for the time of day.

tim