Plummer reverted to the Panthers' practice squad Monday, per the NFL's official transaction log.
The Panthers elevated Plummer from the practice squad Saturday in advance of Sunday's matchup against the Broncos, Darin Gantt of the team's official site reports.
The Panthers signed Plummer to their practice squad Wednesday, Mike Garafolo of NFL Network reports.
The Panthers waived Plummer on Tuesday, Joe Person of The Athletic reports.
Plummer completed 11 of 21 pass attempts for 86 yards and rushed twice for four yards during Thursday's 17-3 preseason loss to the Patriots.
Head coach Dave Canales said Tuesday that Plummer will get a lot of the work in Thursday's preseason game against the Patriots, Darin Gantt of the Panthers' official site reports.