Theft — belonging to another (s.5(3))

A woman is the treasurer of a small amateur football club. Members pay £20 each month in cash, which the woman is instructed by the club's rules to bank into the club's dedicated account within seven days. One month she receives £200 in subscriptions but, being short of money, uses the cash to pay her own gas bill. She intends to replace the £200 from her wages before anyone notices, and she does in fact pay an equivalent £200 into the club account two weeks later. The woman is charged with theft of the £200. Which of the following is the strongest basis for finding the property belonged to another at the time she used it?