You are making a big leap thinking that there are written rules on that.
I guess that every organization that I've been part of has had set rules on how contract notification works with a contract employee. That includes multiple sports franchises, though admittedly not any MLB franchises. Lawsuits have made these sorts of things nearly a requirement of employing a contract worker, sadly. I'm not saying for sure they have such procedures laid out, but with the issues of lawsuits, it'd be surprising that they didn't, especially with Falvey/Levine at the helm, as that's one thing that both have been praised for is their attention to detail in an organization in talking with people around the game.
In many organizations the rules are not just rules, they are laws. That particularly applies to government, health care, and legal issues. Now, such laws obviously do not apply to MLB, but I think more and more organizations of all types see the value of such policies and incorporate them into their rules as they see fit. And these rules are almost always in writing so everyone can read and know exactly how the organization will handle issues that may arise. And that's a good thing. To me it would be a surprise if Falvey (and Jim Pohlad) were not developing written policies for everything about how the team operates.