How can I change the data usage cycle day for Wi-Fi? Changing the starting day for Mobile data was already non-obvious as shown in this answer.

Now, how can I change the day of month for Wi-Fi usage as well? Currently, I have the following cycles cycles:


Jun 6 - Jul 4
May 9 - Jun 6
Apr 11 - May 9
Mar 14 - Apr 11


I would like to change these to:


Jul 1 - Jul 4
Jun 1 - Jun 30
Etc.


How can I do that? I am running Android 4.2.2, Cyanogenmod 10.1 from git. This is a longstanding issue that I experienced with ICS too.
I wouldn't use a stock app to do this. I have tried using the stock app to do data managing and it's really not that great. My Data Manager - Data Usage is a great app that will do fine for your situation. It is free of course, so nothing to lose.

Here is their YouTube video if you want to just check it out.