If it helps anybody who has saved the Ampol offer, you've probably seen it can be used over more than one transaction.
What it doesn't also spell out is that you can use it over more than one location and/or brand. I spent a bit at an outlet branded Caltex, then a bit more at an Ampol on the same card. (They were in different states, too.) Neither transaction was above the offer amount individually, but the combination of the two was then >$60 (the offer amount on that card), and I received the credit promptly. Also, on one transaction I paid using Google Pay, and the other by tapping the physical card. Good to see that all the mixing and matching hasn't mucked anything up!
(For those not familiar, Caltex and Ampol are the same company. Just check that the location isn't a 'Woolworths Caltex' as they're excluded from the offer.)