Yeah if it happens it will be a last ditch move which is why they started with just changing the protocol. I expect though that they’ll try the usual corporate lawsuit shenanigans where they start by threatening legal action hoping the threat alone is enough. Then if that doesn’t work they’ll file a lawsuit but drag the process out using as many tricks as they can come up with to ensure it never goes to trial in the hopes of either bankrupting them or forcing a settlement. If they can convince a judge to issue a temporary order to cease operation that would probably be a home run from their perspective.
Where the really interesting part starts is if they run out of tricks and it looks like the case will actually go to trial. I expect at that point they would try to drop the lawsuit, but Beeper might not allow them to. That would be really bad for Apple for all the reasons to outlined even if they ultimately win the case.