According to ProFootballTalk.com, the NFL is already in the process of setting up a free agent "signing day," in which unsigned NFL players would announce where they are deciding to take their talents, just like high school players do with their college commitments.
From PFT's Mike Florio:
As former Chiefs G.M. Scott Pioli said during Thursday’s edition of Pro Football Talk on NBC Sports Network, the NFL hopes to create a “signing day” for free agents, similar to the phenomenon that has arisen in recent years regarding the date in early February on which high school players pick their college destinations.
We’ve confirmed that the NFL has specifically proposed a “signing day” in communications with the NFLPA regarding a revised offseason calendar. As Pioli explained, the new three-day legal tampering period is aimed at setting the stage for a one-day bonanza of announcements of new destinations for free agents.