Display issue during route navigation
In both cases, it occurred in the vicinity of the M4 motorway during the exit, and on approach to the entry.
Given the choices of lanes, and possible routes at those points, direction became vague.
Once leaving the immediate area, the display resumed normal operation.
The screen shot above refers to entry into the motorway "2nd issue" in the map reference below.
I have never seen this effect in any other instance of use in this application, and wondered if it was an issue with the map data…