I'm starting in June too. I asked HR a couple of months ago about the pay, and they said what Gonzo said for whilst you are at the college, but they said you earnt about 23K - 27K while validating, depending on what unit you're at. Perhaps this is from 19K or so with unsociable hours payment?
Anyway, for those with kids, you would possibly be entitled to Working Families Tax Credit to help out a bit.