I don't know how much (if any) control of signalling has been transferred into the ROC at York John, but the Kings Cross station control room, if as it was 4 1/2 years, is a control (co-ordination) and recording of CCTV, station radio, and 'phone communication facility only, staffed by (as featured in the TV prog.) personnel of Network Rail, and Virgin Trains East Coast (and I presume, as one would've thought, GTR Great Northern), and has VDU displays of train positions by headcode, from the network's CCF system or some derivative thereof.
Control of the ECML signalling from Kings Cross - Biggleswade remains (for now) in the 1975/7 KX PSB.
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