Plane mode - distance to DZ unit of measure

Device is set to ground speed in knots, distance and altitude in feet.

My second time using the device yesterday. One the first day in plane mode, the distance to DZ was showing in miles e.g. 1.5 miles. Yesterday, this same measure was showing a four figure reading e.g. 4000 which incremented as the plan circled the DZ and then flew the run in. Not sure if this has changed to metres (i’d have thought it’d show KM). Checked device settings on landing and all showing knots & imperial.