yes it is , by 2029 supposedly ,that's another 5yrs
https://forum.zorin.com/t/end-of-lite-versions-announced/37442
looks like it safer to do a clean install...
https://forum.zorin.com/t/is-it-possible-to-make-a-complete-switch-to-xfce-in-zorin-core-if-yes-then-how/11337/10
this is just my searches to help you make a decision , it's no way my recommendations.
and for my curiosity i found this too 