Take a look at this 25.10 roadmap: Ubuntu Desktop 25.10 - The Questing Quokka Roadmap
There is some information about improvements to TPM-FDE through the new “Security Centre” app which allows you to regenerate your recovery keys.
However, I don’t know if this also replaces the key stored in TPM.
I asked a similar question maybe a year ago, but at the time there was no way to do it.