Steve Naïve writes
See stuff on the TOCU for more info...

TOCU? (train operating companies ...???)

Possibly 'Transport Operational Command Unit', a collaboration between
TfL and the Met Police.

There will probably be some info about it on one or more of the
following;
www.tfl.gov.uk
www.met.police.uk
www.mpa.gov.uk

--
Dave