It’s still uncertain but the talk may have been at: Chosing the right modem PLS8 vs BM818 and follow the links.
Depends on which country - and whether the database (web site) is kept up to date.
Depends on which country - but if the data is there, I would expect it to be public i.e. where this is licensed spectrum, and a matter of public record.
The T1 have all band of the E1 except B20.
In France, providers use a lot the B20 band but also more and more the B28 one.
It’s a shame that no model is supporting the 2 bands…
Thank you very much for making this available! This is really great news! And congrats on the shipping announcement! 
Yes.
This is basically completely outside the control of Purism - but I would like to think that if and when a compatible global / world (all bands) module is released by either of the two suppliers, or any other supplier, then it too would be an available option - even if it were at a modest premium.
Did you already check cellmapper.net? With this map you get more granularity in which areas (exactly: station) which bands are supported. This helped me a lot to figure out, that B20 is very important to me and therefore T1 is out of scope in my case even with higher overall band coverage.
It can potentially help you decide whether to go for T1 or E1, because you know that one band is more important to you than the otther (B20, B28).
It’s clear that E1 is better than T1 in my case but there are more and more B28 antenna. I don’t know if it will be problematic or not in 2 or 3 years.
in 2 or 3 years if this ‘show’ keeps up there might be something better and because the modems are modular (basically a modem slapped onto an m2 card) they can be donated/sold to someone else without much fuss …