Please help?!

Has anyone claimed the 30 hrs and lost eligibility ??? I don't know how it works my partner lost his job and didn't tell me for two months  just pretended to go to work. We claim the 30 hrs for our youngest. When I found out in june I asked him to leave I couldn't believe how much he'd lied I pay all the bills as I earn more and I thought he was just getting the weekly shop and putting money away as usual as he's weekly pay  turns out he's spent any savings he had keeping up appearances. He moved in to his mums but we have since had counselling and he has admitted he is suffering with depression and is now on medication and a program and wants to move back in to help with childcare over summer.  I have agreed to this as our youngest starts school September. All our children believed he was just staying at nannys for a bit to help her out.   I just don't know how I go about sorting this 30 hrs out everywhere just says you have a grace period but it's not clear on this at all?! How long is it? Who do we call? do I know owe any extra?  So confused!