@Randy Calvert thanks for the help.
It is on PHP 8.2, my original 7.4 comment was wrong.
The monthly updates up until this one have all installed just fine.
My site was setup and installed 10+ years ago by someone I hired to do it. He's no longer around to help so I've been managing the site ever since then by myself with my limited knowledge.
I've never had to do a manual upgrade in all the years of running the forum. 😟
My site is currently restoring a backup from yesterday. Once that is complete, I'll attempt the manual upgrade.