semi-conspiracy theory: the main goal of this rewriting is to have less and less infrastructure depending on GPL and AGPL-licensed code
There are a lot of tricks needed to make the above work, and details that you need to consult a lawyer and accountant for.
but if they develop it for internal usage only, then they don't get the added benefit of destroying the existing copylefted version!
I'm also curious if they will accept GPL or not
"Insecurity is freedom."