I made a post about losing RCS support in Samsung messages after 6.1.1 update, and shortly after got the information i needed to get it back working, so I wanted to make a post to share what I found. May not work for everyone but I fixed it in two steps.
To use RCS in Smessages:
Turn on ALWAYS ALLOW in 'use premium communication services' found in
Settings > Apps > 'Special Acccess'
Turn OFF RCS in Google Messages
Reboot.
I'm on a Galaxy S23 Ultra using TMobile.
