Spend $49 or more in a single transaction on your Westpac Credit Card by either the primary or secondary cardholder. Limited to 1 cashback transaction(s) per merchant, per card and will be paid into your account within approximately 7 days. Offer is valid online only. Offer cannot be used in conjunction with any other offer. Offer valid only for eBay Plus annual membership. Not eligible on monthly memberships.
It looks like it is only for Ebay Plus annual membership payment, but how Westpac knows ?