The week number is (somewhat) used for navigation, but the way it is used is not affected in any way by the rollover, and there's not really a way (even taking

The week number is (somewhat) used for navigation, but the way it is used is not affected in any way by the rollover, and there's not really a way (even taking into account bugs) that not knowing what the current GPS epoch is could affect navigation. This is purely a matter of an issue with the time that's output for human consumption, the GPS functionality itself doesn't care in the least.