I'm working with a number of families in real hardship because the Tax Credit Office hasn't processed their claims and they're 4+ months down the line. All the necessary information has been submitted and each time the helpline is called it's the same old thing...it's with the TCO but they don't have time scales so there's no estimate of when the claim will be paid.

Does anyone have any phone numbers for the processing teams at HMRC?

I have never heard of anybody who has got hold of their direct numbers. But there might be an indirect solution. Here in Liverpool, if there is a delay in paying a claimant's tax credits, they can go to the local tax office in the city centre with proof of their identity (passport, driving licence, jobcentre letter) and get paid over the counter by girocheque. They get either one or two weeks' money at a time and it is meant to be a temporary measure while they are waiting for the tax credit payments to be paid regularly into their bank account.
I don't know if there is a similar facility in any other part of the country, but there should be. The TCO don't advertise it, I only heard about my local arrangement 'on the grapevine' through another adviser.

over here, i know people sometimes come to the tax office (co-incidentaly upstairs from me....) if they've been having trouble, and do get over the counter cheques...

but i gather from the original post that the decision hasn't been made, rather than decision made & no money?

...that's right...decisions are taking far too long to come through, and when I phone the TCO they seem to think there's nothing wrong in not having a time scale to resolve a claim.