IIRC it's 4 weeks after the duration of the injury settlement. So if the Packers, upon release, paid him 3 weeks of salary as an injury settlement, 7 weeks after the settlement the Packers could sign him, but any other team could sign him after the 3 weeks of settlement. Note I was just using the 3 weeks as an example, I don't know what the actual settlement was.
Fire Murphy, Gute, MLF, Barry, Senavich, etc!