How to clarify the data usage sequence?

FC

I thought I knew the data usage sequence before (check the date remaining). But I am lost now. Yesterday, I activated a 500M perk for one of my number as it was very low. Today, I checked, this number used about 150M data. However, I found this (see the picture). If I was right, this 150M data should be from "230.46MB Rollover" data, and this picture should have 80MB for Rollover (230MB - 150MB = 80MB), because there is "1 days left"; and the bar of "500MB Perk“ should be full. But it is not the real: that 150MB data was used from 500MB Perk. In conclusion, it seems the data usage sequence is NOT on the "days left" - (Perk use first?). Is it correct? Just want to confirm this.

Olivier R. #3666

Gift perk and bonus go first, normally monthy date plan goes last.

André L. #16536

Priority of data usage consumed is:
1. Fizz perks
2. Data received from friends
3. Allotted data in your monthly plan
The priority does not take into account the expiry date if these categories.