Now that Brett Favre has been reinstated by the NFL, the Packers have to act within 24 hours, and that means a roster change.
If the Packers don't either trade Favre or come to some other arragement with him, he'll have to be put on their 80 man roster. That means some poor soul is going to have to be either cut or put on injured reserve.
More than likely they'll wait the entire 24 hours. They probably don't want to cut anybody before tonight's Family Night scrimmage. They'll want to give players every chance to prove themself before they make any cuts.
Any serious injury that pops up tonight, God forbid, could also affect any move the Packers make. A torn ACL means making room for Favre would be an easy proposition.