NHL teams will submit their protection lists on June 17, which is followed the next day by a valuable 72-hour window in which the Vegas Golden Knights can negotiate and/or sign any unrestricted free agent in the NHL, and any unprotected restricted free agent who is otherwise eligible for the expansion draft.
Any player who is signed will count as the team's selection in the expansion draft, which will be completed at the end of that window, on June 21.
It is an incredible advantage for the Golden Knights, because it removes a lot of risk. Without this opportunity, imagine if they were to select a high-profile free agent like Kevin Shattenkirk in the expansion draft, but fail to come to a contractual agreement by July 1, at which point he becomes free to sign with any team. That would mean that they wasted one of their 30 picks.
This window allows the Golden Knights to open negotiations with Shattenkirk two weeks before any other team, and then make him the team's selection from the Washington Capitals if they arrive at a deal, or select someone else if they don't.
While Shattenkirk is one of the more obvious targets for this window, who else might be a good candidate?