Most I’ve seen seem to think it’s a good move for him. He has his own thread on arsenal-mania although no one has posted since today’s developments.
https://arsenal-mania.com/forum/threads/cozier-dubery-its-a-me-amario.36311/
Don’t think there is anything wrong. Arsenal seem to want to keep him. Probably believes he has more chance of first team elsewhere with Bukayo Saka ahead of him. Newcastle apparently interested too.
Deals cannot be processed on 30 June itself, as it is not a working day, so some transfers may not be confirmed and registered until Monday. The clubs can submit the deals in their accounts for the year if they can show the agreement was in place. At least that’s my understanding.