They should probably have a clause that states nobody can leave too, surely.
I don't think that would be possible, may be wrong though. Russia/Sweden/China off the top of my head have different windows to the 31st August deadline and I don't think any of them have that clause. So in theory the shortening of the window wouldn't make any difference to players being on strike etc if a foreign club is the one unsettling them (like Coutinho for example).
