While the official transfer deadline is the only official one that can stop a transfer from going through, it does make sense that we are starting to see clubs imposing their own deadlines for selling players.
The last thing any time needs is extended uncertainty over their best players, while it’s going to be almost impossible to find a top class replacement for anyone at this time in the window.
Arsenal’s chase for Lyon star Houssem Aouar has been going on for a while, but the reports from France have indicated that they were told of a deadline to get this deal done, and they’ve left it too late:
Lyon source to Le Progrès: "The deadline has past – neither Memphis nor Houssem are going to leave. They will train today & be in the squad tomorrow."
— Get French Football News (@GFFN) October 3, 2020
Aouar has still been playing while the speculation was going on but his form has been affected, so it always looked like the club would need to make a final decision one way or the other.
This should put an end to the speculation and you feel Arsenal would’ve completed this deal by now if they had the money, but it’s likely that there’s still going to be more to this story.