do I need to tell Tax credits now?

My DS ages 3 goes to nursery 3 days a week. We nowthe free hours towards the fees which has lowered the cost of nursery per week. We are also now using vouchers throug work towards the fees. On our TC claim is says the previous amounts for childcare costs but we do not recieve any childcare elelment on the award. Do we need to tell them now (and will it affect anything if we do not recieve any of the childcare element) or can we just wait for the renewal?

Calling them always takes hours!