[Garlon]

You are toggling a feature, and it is working as designed.

The game will hold on to any experience gained each progressive season. You cannot undo the toggle because the game is not keeping all of those old values in memory. It simply overwrites them. So, when you toggled Aaron gained positional experience and when you toggled again it remained. The game did not hold on to what you had before and there is no undo button.

You could edit the experience and type 0 and press enter and it will save that if you want.