I read "From 2019..." to be be the start of 2019, which isn't too far away. I would use Prime a lot more if I didn't have to keep plugging the PS4 in.
Amazon coming this month apparently (Now TV is from 2019)...
Prime Video is coming to BT TV this month, giving the firm’s customers easier access to exclusive Amazon series such as The Grand Tour and The Man in the High Castle.
Better info here :-
Even better if it is this month, maybe BT's Press Release means 2019 as having the full suite. The BT PR is a bit vague to be honest, I would have thought if Prime was going to available at least 6 months earlier you'd say so wouldn't you?
Will you have to subscribe to BTTV to see the Prime Video app or will a YouView box simply connected to a BT connection be enough or will it simple just appear on all YouView boxes like the Netflix app did.