I have been using Thunderbird for many years and am happy - if not perhaps delighted - with it. I went to update my Ubuntu distribution to 24.04.1 LTS the other night. Apart from the fact that the upgrade broke my system and I have had to do a clean re-install, I also got a message to say that from 24.04.1 Thunderbird will only be available on Ubuntu via snapd.
My questions are:
Is it possible to install Thunderbird without using snapd? I remember a few years back that you could do something to avoid snapd for Firefox in order to keep up to date with releases (Ubuntu snapd releases lagged behind FFX by some way)
Is this something connected with Mozilla stepping away from TBird? If so what are considered the viable FOSS alternatives that would allow me to transfer across my tons of mail and folders without pain? If not what are the next best things.
I have done a lot of digging around and don't seem to be able to come up with a clear answer, but I may have missed something.

