@Raymond_Sickler: I like, you went on and upgraded your system - good one! 
For other users wanting to upgrade their system, here’s the official documentation with full detail:
FreeBSD 13.1-RELEASE Installation Instructions
RoboNuggie just released a video about FreeBSD 13.1 (link with timestamp)
Last part is about upgrading a system, but he brushes over the merging of /etc/groups - look at @tthenrie’s post above for that part.