As part of the new Collective Bargaining Agreement regarding COVID-19, NFL teams now have the ability to protect four practice squad players from being signed until after the next game. This allows teams to protect positions on their active roster that could be thin in the event of a positive COVID-19 test. Then, players can be called up to the active roster at any point between now and when inactives are due 90 minutes before kickoff.
In Week 1, the Bills are pretty healthy across the board and with depth very good to start the season, the team chose to protect their top level of practice squad players instead of focusing on a position group.