I'll have to check my partner's pixel 3a when I get home from work then, she's on the latest build of android also, but with Optus though, lol amaysim uses Optus network so it shouldn't matter, I'm currently using a Surface Duo, that uses Google's messages and phone application out of the box, so I'm hoping, this RCS rollout is the REAL DEAL, from Google.
Few people over whirlpool thread have given some tips. Like put your phone on flight mode, clear data and force stop both carrier services and messages, reboot the phone and then jump in messages, you should see pop up. For me I didn't have to do any tricks I just jumped in the app and pop up showed. Also neither me nor my wife running beta version. Cheers
I can confirm 100% that my partners pixel 3a has RCS messaging connected, on Optus I didn't do anything, just checked the chat messaging application settings and it was saying connected in green, maybe Pixel devices first then the rest, just to repeat I didn't do any hack or reset or anything, we have our Google messaging application on the betas, hers is working now just hoping that my Surface Duo will receive the same update soon, it's all internal Google's rollout 100%, as the stooges on here for customer service have no idea.