Aug. 24: McCoy accepts a reduced salary. The news comes out a day later, at which point McCoy confirms that he accepted the reduction on Saturday night, the 24th.
Aug. 25: McCoy completes 11 of 15 passes for 109 yards and an interception during the 49ers' preseason game against Minnesota. Wallace hardly plays. After the game, Harbaugh tells reporters he "feels real good about Colt as the backup quarterback."
The timeline suggests Wallace's signing helped the 49ers secure a pay reduction from McCoy while providing insurance. That may or may not be the case. We know Colin Kaepernick is the starter and McCoy is the heavy favorite to serve in the No. 2 role, and that Wallace could have some additional time to learn the offense -- perhaps so the 49ers could turn to him later if a need arose.
Teams have until Tuesday to reduce their rosters from the 90-man limit to no more than 75 players. The mandatory reduction to 53-man limits is Saturday.