So I have been facing the same issue, I tried to override the warning by adding a speed driving alert but that did not do anything. I called customer support, and when I told them about my situation they said they have no clue where it could come from and that I should visit my dealer about it. This started to happen when I updated both the MySubaru and Starlink App, and updated my infotainment system. So it could be possibly an App issue or software issue, because I only use Apple Maps, and in my maps I have it custom to the way I want it. I have been looking up anything about it but nothing, so I hope in time both the developers of the apps and infotainment system catch ear on this and find a solution.