Originally Posted by Exo.
as the rest of the routing (back from Elstree) is via the City CTR (which I think was closed at that time, and therefore called the London CTR as well, confusingly).
London City was open (they opened at 0630) however, AIUI movements were reduced due to de-icing because of the FZFG (visibility at London City was 700m at the time of the accident, and 600m when PB departed from Redhill).
The City CTR (and CTA) are H24 and are always called "the City Control Zone (and the City Control Area)".
It used to be the case (prior to 9/11) that when London City were closed, the City CTR (no CTA existed back then) reverted to Class G but it was never called the London CTR. You maybe confused because outside the hours of Thames Radar and Heathrow Radar, the Controlling Authority becomes Heathrow Director.