I used to fly in the '70s around Cincinnati, and back then the isogonic line (zero magnetic deviation between magnetic and true North) passed almost right through me home airport. Now there is some 4 degrees deviation in that area.
The magnetic north pole is indeed moving, always has. Somewhere along the line they may need to start relabeling runways and stuff. I suspect the pole switching is something that doesn't happen suddenly, but over a long period of 100s or 1000s of years..