It won’t be an issue as manufacturers of navigation systems would have to be aware of the constant movement of the magnetic pole in order to make your cycle computer. The movement is not something new.
I think some GPS systems for bikes use magnetic sensors in conjunction with GPS so they should update. If they are using only GPS the satellites use a different system so it won’t affect anything,
I’m not familiar with cycle computers but if they are GPS yes they will update. The shift of magnetic pole is a constant movement and before modern aircraft had electronic navigation systems and GPS, pilots had to calculate the deviation between magnetic and true north before each flight. Pilots carry a flight plan with the route plotted manually so they can calculate the deviation manually if instruments fail.
No need to prep because scientists know that the pole has always been shifting. Navigation systems such as those used by pilots of aircraft are regularly updated to account for the shift of the magnetic pole.
The change is gradual and by updating the navigation systems that use magnetic North for guidance it is easy to integrate the changes.
For most people I doubt there will ba any day to day impact, industries that rely on navigation can easily update their systems and for nature there is some minor influence for the more northerly species that may use magnetic navigation but their senses are probably sufficiently vague that it won't really cause enouigh of a problem to be noticable,
