@yuu-ä3 System settings offered the upgrade and unwisely I applied it only to find the phone more-or-less bricked. After a few false starts (see my posts) I was able to restore 20.04. My advice: DON'T TOUCH 24.04 on OP6 or 6T until there is an announcement about the port (Unless you are able to contribute to the porting work)

@Wheeling-Pigeon Indeed. And either 9S/Pro/India...All share the same motherboard hardware&firmware + same built image...

@MrT10001 I did not use trwp just local update. But I did get it to go. I reset the phone, used the zip from the XDA link you put, then used a different computer with a fresh ubuntu install, flash UB24 from there it booted into recovery, I then flashed UB20 from the installer and was able to update to 24. Not sure why that worked but it did. Thank you for helping. EDIT so I posted that while it was updating to 24.0 and it rebooted right back to recovery and that was it, I was able to re flash 20.0. So I assume 24.0 just does not work on the 6t as of yet, which is cool since it is still new.

@domubpkm said in How to use volte: I speak of Volte in this case, I can confirm you that the people who defined VolTe (the businesss associations working on this standard) are most definitely not bothering with the interactions of UT and Bouygues, this is far far below their field of concern