This might be the most Harbaugh-like thing that I've seen someone not Jim Harbaugh do.
They're taking advantage of a loophole that allows you to declare and go to the pre-draft combine, if invited. Kids have up to 10 days after the combine to withdraw their name and come back to school.
You still cannot hire an agent. But you can do this up to three times.
It's legal. It's within the rules. It's something Harbaugh would do if he coached college hoops.