[Baggiebob(BBB)]

The transfer window for signing players players has ended.  The loan window is now open until the end of August, so a club can bring in loan players from anywhere up to that date.  Out of contract players can be signed at anytime I believe.  Many of the European leagues transfer windows are still fully open, so they can still sign players from English clubs, we just cannot buy from them.  

As regards the 25 man squads, I believe that is only a PL rule, never heard of that being used in the EFL.

 Thanks for all your answers. That clears that up for me.