I thinks it’ll a player power play.
It’ll enforce clubs to put their best contract offer to the player early, establishing clarity for the player and shifting the blame to the club for low balling contract offers.
As WillG said agents & clubs will negotiate whenever they want but signing will be in the permitted windows.
I argued that it’s probably not legal to restrict when contracts can be signed but got hit with the (catch all argument) “the specificity of sport” argument.
f***ing lawyers,eh!?