In terms of studio space, there is no further studio space available at ITN. They have only four main studios. Studio 1 and 2 in the basement are used for the ITV National News, ITV News London and Channel 5 News with the Channel 4 News based in their atrium view studio. Along with a small CSO studio for emergency, there is not really any more studio facilities at ITN, so it makes sense that it is just office based staff and departments which could move into Gray's Inn Road.
As far as I know there are currently 3 TV studios at ITN. Studio 1 (ITV), Studio 2 (C5 & The Wright Stuff) and Studio 6 (C4). Don't know what you mean by a small CSO studio for emegencies - I've certainly never seen one unless it's very new. Not something I've heard about though. Unless you mean Millbank?
Although the rest of the space is mostly offices and control rooms, that's not to say that they couldn't create new studio space if they needed to. Studio 5 and PCR5 that were originally for 5 News in 1997 had been completely removed. But that didn't stop them re-creating PCR5 when 5 News moved back in 2016. And in fact it's now in the basement of the adjoining building rather than 200 GIR.
I think a distinction also needs to be drawn between ITN and 200 GIR (
http://www.200gir.com). When it was built, ITN owned the whole building. But that's not the case anymore - many other unrelated companies are housed in 200 GIR. ITV have/had some management offices higher up the building, not connected to ITN. Anything moving from
TLS may potentially end up on a floor that isn't owned by ITN. Remember, ITN is a separate company whose client is ITV.
Last edited by itsrobert on 28 March 2018 10:42pm