Data Usage - not possible to chose my own cycle

Unfortunately the topic “Data Usage Cycle FP1” doesn’t match.

My Phone is an FP2 with the operating system FPOpen 16.08.0.

So I like to set my own Cycle for the Usage of my Mobile Data in the Setting Data Usage.

At the moment I can only chose the cycle provide by the Android System. Unfortunately even these dates aren’t always the same.
Today (09/23/2016) it provides me 09/10-10/9. Last week on the 09/16 it provides me 08/17 - 09/16. But it provides me always the cycle in the past from 1970 - which is nice :wink:
Anyway I want the cycle 08/26 to 09/25. Next Cycle would be 26/09 to 25/10 How can I enter this cycle? Are there Settings which do not show up in the Menu Data Usage?

ps: the dates are written in mm/dd/yyyy

There is a bug report here with a description how to change the cycle:

https://forum.fairphone.com/t/changing-data-usage-cycle-not-possible-by-default/20426?u=paulakreuzer&source_topic_id=22249