I would think any "deal.... done" isn't contractually finalised and the buyer, or seller, could find reason to pull out before the window opens and any deal finalised.
No idea how it works, but I'd have thought it possible - for sake of argument - for Eze, QPR and Spurs to sign a deal now, which is binding, with the player registration only switching when the window opens. Or is that banned? Genuinely not sure, just assumed you could.
