WTC Employment Gap

Maybelline_Eyes

3 years ago, my husband was made redundant and he had a 13 day gap between then and finding a new job. It was almost at the end of the tax credits year (i.e. March). At the time we read the notes that accompany the WTC award and i am certain it said you had to tell them if the gap was 14 days (it's now 7).
3 years on and the WTC have chased us for an overpayment. We'd done everything right (notified loads of changes of circumstance on time)except notify them of that gap. Because of the gap they didn't process our 2005-6 claim and have sat on that ever since, despite us reapplying 3 times at their request, so that we could offset the overpayment against it (for which we were entitled to claim but have been paid nothing). They have now said that we cannot do this.(Although i had a phone conversation with them in which they told me we could and a letter from then confirming we could, which they also have a copy of) They now say we must pay up first and only then will they process the 2005-6 claim. No explanation of why they sat on the claim for 3 years, nor why they are reclaiming after over 3 years!

We're now trying to put together our next appeal and i wonder if any of you have the notes from 2004 that say the gap in employment could be no more than 14 days? (that's the green page that comes along with the award)
Alternatively if anyone could point me to somewhere online that says when that time period changed?
It's a long-shot i know, but thanks in advance!