This is feature of OXCE, we can declare that some functionality will be deleted at some point, and madders have time to prepare.
Before given year, game only warn, on given year game will reject load of given mod (still can be overridden by user) and finally after given
year, functionality will stop to work even if user try override it.
And yes, it use version time as it easy to predict.
Another bonus is if you compile old version it will behave exactly same as before.
Why code like this is needed? Some times fist version of functionality was lacking and was replaced by lot better version.
Another thing is some old code prevent better version in future.
This allow us to remove some old bad code and give most of mods time to adapt to change.
