You'll have to wait for something offical on twitter
but in essence, it doesn't make much sense that Jolla is taking away freedoms they themselves use and have used to prototype their own systems on devices.
Flashing own kernel and own OS and getting to keep both pieces if they break as a principle, is entirely fine with me, for example.
Read everything together in context (both text and target audience) instead of just those lines and things look darned much better.