Mike Vandermause brought up a really interesting point about undrafted rookie free agents in his latest chat at the Press-Gazette. Just as veteran free agents cannot be signed, undrafted rookies can't be signed either, until there's a new collective bargaining agreement. The Packers did really well with two undrafted free agents signed last April: LB Frank Zombo and CB Sam Shields.
The idea that all the rookies would be swept up in the scramble to sign all the veteran free agents could make late April a chaotic time. The Green Bay Packers aren't at a huge disadvantage, all the other NFL teams would be in the same boat, but I wonder if the Packers (or any other team) might look at the pool of unrestricted veterans available and go with fewer rookies. That might make it even easier for the Packers to target all the undrafted rookies they were targeting.
There is no correct answer here. I'm just looking ahead at what could be a unique time in the NFL. The Packers have a great front office, in the college and pro scouting, and I'd expect they'll put together the best roster they can assemble, no matter the circumstances.