Au Pair upfront fees

Hi, if Au Pair agency fees are paid up front in 2019, are these eligible to be apportioned over the tax years? For example, if my au pair was from 1 July 19 thru 30 June 20 i.e. 6 mths in each of 2019 & 2020, could I apportion the agency fee 50/50 across tax years?

 

Thanks