Allen (concussion) is participating in practice for the second straight day Thursday, Joe Buscaglia of The Athletic reports.
We have to assume he's participating to the level the league's concussion protocol allows, though Allen working with his teammates does suggest he remains on schedule with the protocol. Typically, players have to pass each of the stages with no delays in order to play the following week. We'll have a much better read on Allen's ability to play in Sunday's game against the Titans as Friday and Saturday roll around. If he has a setback or the team decides to go the safe route, Matt Barkley would get the start against Tennessee, while the Bills have a bye in Week 6.