Are you talking about Scheduling or My Aircraft screens?
On scheduling, there are 2 things:
- click to change registration
- hover to bring up pop, from where you can select view aircraft
If I understand correctly, you want to add link on the hover pop up to change registration. But I see it as redundant. Why do the same thing with 2 steps, hover and click, when you can do it in 1 step: click?