A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Geoffrey Kolbe
Date: 2019 Mar 31, 22:19 -0700
For what it is worth, here is Garmin's take on this potential problem:
"For GPS devices that are affected, after the rollover occurs, an incorrect date and time will be displayed. This incorrect time will also be used to timestamp track logs, compute sunrise and sunset, and other functions that rely upon the correct date and time. However, the positioning accuracy will not be affected. The device will continue to deliver the same positioning performance as before the rollover."