Ports Collection support for your FreeBSD version has ended...

From: Milan Obuch <freebsd-ports_at_dino.sk>
Date: Fri, 02 Sep 2022 06:09:13 UTC

as I am doing today some maintenance, I am encountering this error.
This would not be worth mentioning, it is easily overridable by
defining ALLOW_UNSUPPORTED_SYSTEM, just I got this error on a
13.1-STABLE systems built relatively recently, one of them is built on
June 3, 2022... this is extremely prematurely in my eyes. Note this
does not happen on 12.3-STABLE system built on April 10, 2022.

If there really is some important issue in recent 13.1-STABLE system, I
think it should be mentioned and announced somewhere.