UltraGauge (2011) service display quirk

[California98Civic]

This photo shows the odd Service Distance reading I have had on my Ultragauge for a long time. It shows -4 miles in the photo. That is the near-end of a count down from 30,000 miles. The device first counted up to 30,000 miles from zero when I bought it in 2011 and ten began counting down from -30,000. This month, it finally reached zero and has started counting back to 30,000.

Odd quirk.