When petrol prices start to go up it's a good time to fill up and take advantage of the discount voucher. The next thing I do is lock in the lowest price for another week using the 7 Eleven app. The problem with the 7 Eleven app is I tend to jump the gun. I lock the price in once the prices start going up. However, if I wait one or two days I can push the 7 day time limit out a couple of days.
Today I decided to do a test with the 7 Eleven voucher and see what would happen. I'd lock in 116.7 two days ago. I knew of another 7 Eleven with petrol for 115.9. What if I filled up my tank now and then locked in the lower price. That would enable me to extend the discount period by two days.
I topped up the car with around 10 litres at a 7 Eleven with a price of 139.9. I got the discount for the locked in price of 116.7. It took perhaps around 5-10 minutes before the 7 Eleven app registered the voucher had been used. I had to display the voucher again and at this point the 7 Eleven app was ready to lock in the new lower price. I then locked in the new price of 115.9. That saves me a little more money and extends the voucher expiry date.