Didn't get anywhere with SMS/mms.
I've tried turning off RCS in my messaging settings but the messages still come through to my old phone, still signed in to Google account.
I can send an SMS with the UT phone but the reply goes to the android phone.
Any advice would be much appreciated.
Thanks all.

@lduboeuf thanks for your reply.
I disabled RCS in my Google messenger settings but didn't make any difference.
I'm not sure how it works, if someone else has RCS turned on & I have it turned off so I still receive the message?
The little testing I did with RCA turned off and messages from my wife's phone (RCS on) went to the android phone & didn't appear on my UT phone.

New user to UT and so far I'm pleased.
To test things out I bought a pixel 3a preloaded and got started.
Most of the basics are working fine although I note the lack of apps for focal as opposed to xenial but the big issue for me is none of my sms/mms messages are coming through.
I'm wondering if this is due to the lack of support for RCS?
I'm moving over from Android, so RCS is enabled by default, turning it off won't help as the sender would have to turn it off too.
Is this a known issue, is there a work around?
Thanks all.