A warning here. I blew over 330 Qantas points (via EDR) at a Caltex service station yesterday because I handed the operator my MyerOne, EDR and AMEX cards all at the same time. He swiped the MyerOne card first.
It turns out that if the EDR card is not swiped before the MyerOne card, you can not go "backwards" and swipe the EDR card. You also cannot cancel the transaction once the MyerOne card has been swiped.
As such, I will now use this method when paying for fuel
1. Provide EDR card and wait for it to be swiped.
2. Provide MyerOne card
3. Provide AMEX card.
It turns out that if the EDR card is not swiped before the MyerOne card, you can not go "backwards" and swipe the EDR card. You also cannot cancel the transaction once the MyerOne card has been swiped.
As such, I will now use this method when paying for fuel
1. Provide EDR card and wait for it to be swiped.
2. Provide MyerOne card
3. Provide AMEX card.