I was able to keep all the 2016/17 squads and free agents by launching the vanilla game while the updates were downloading, and changing the squads a little (like moving Gabriel Jesus back to Palmeiras). That allowed me to create an edit data save, and after the updates were implemented, the game restarted and made a backup edit data save, and asked me if I wanted to update the squads. I said no, and ignored their squad update, thus having the original squads (Totti, Cambiasso, Lacazette in Lyon, Ederson in Benfica, all the other good stuff). The newest squads can still be used by allowing the live update while choosing teams. And if anything happens, I have the backup data.