To everyone who has a note saying that they need more documents:
It's not necessarily the case that they do. Someone mentioned a system glitch and I think that this is probably the case unless you've been contacted about more info.
Mine has been stuck on that for a long time and I queried it once when I phoned but the operator couldn't tell if they actually needed more info or if it was just an issue with the system. She had to send a note to the person processing it which takes a month to read apparently. We have had no further information requests off the back of this note.
So if everything is going ok I wouldn't worry too much.
But I guess if you have a good long distance phone plan and an hour to spare there's no harm in calling