Yep, this was indeed the problem. At least its an easy fix. Thank you for that.
"League date 15/9/2040 generated for (competition) is not in year range 2019 to 2021" I've been trying to restructure Australia and all of my season dates seem to be right but in testing the editor is trying to stick in a date twenty years in the future. I can't find 2040 referenced anywhere in the rules for the nation or any of the competitions. I've attached the file if someone can take a look. Aus Restructure v3.fmf