One of the reasons I wait is that our receipt is supposed to include our SIN number - see other threads on this. When a family is leaving in anger is not the time to give them such personal info. It also makes them come back to me in the new year sheepishlly or whatever to ask for the receipt. By law I must make it available - I do not have to mail it to them. They must come and pick it up - evenings only when hubby is here.
Now having said that I do give a receipt with each pay period so they would already have that and could use those. They wouldn't have my personal info but so what. The statement I give in January is a yearly compiled by monthly one page statement.
I can see where if you don't do regular receipts they want something now afraid you could move and not be available come January. I probably would give them a simple reciept ( I just use a book with tear out statements even the dollar store carries). Do not give them any info like your SIN just the amount and dates covered.