No, I'm actually confused by old posts in the ITV News thread! Some say there was two ITV News sets, others say one.
It might be better to quote the posts in that thread rather than cause a new confusion, though I think if you read through them you'll find the answers there.
ITV News has one main set but has decamped to the other virtual studio from time to time when they can't use their own studio for whatever reason. Studio 4 is for C4 News, Studio 5 the old 5 News/Setanta Sport set and then I think Studio 6 is London Tonight. I think we concluded Studio 3 was the old ITN set for the Early Evening News which was in the newsroom towards the top of the atrium.
Not quite, Brekkie. Studio 4 is London Tonight and Studio 6 is Channel 4 News, not the other way round.
To sum up:
Studio 1 - virtual studio currently hosting Channel 5 News. Used to house ITV bulletins until 2004. Controlled by PCR4.
Studio 2 - current ITV News studio. Controlled by PCR1.
Studio 3 - no longer exists. Like Brekkie says, we decided it was home to the Early Evening News in the early 1990s and was probably taken out in the mid-1990s. I think it was on a floor which ITN no longer owns.
Studio 4 - London Tonight. Used to be ITN News Channel and ITV bulletins in the late 1990s. Controlled by PCR2.
Studio 5 - no longer exists. Used to be home to Channel 5 News until 2005 and then Setanta Sports News. Was controlled by PCR5.
Studio 6 - Channel 4 News since 1999. Controlled by PCR6.