Bad news for anyone not with Prime who signed to BT in expectation of rugby though. Makes existing TV packages worse, as BT will replace rugby with more obscure Bundesliga football, so you will have to pay twice until your contract expires. Meanwhile what about European Rugby? If that stays with BT then that is yet more subscriptions to watch the lot.
If Anazon want rugby then buy lot, so that we can get it in one place. Lions, 6n Ai, Europe, all of it. More fragmentation is not good for the consumer.