@Dave if you navigate as if you are going to buy, you can put in a value of 1 for units - it won't charge you yet - then <continue>. The next page should show you your current end distance (ie what you have paid up to already).
@flambonkscious@Dave The guy who services my car told me many moons ago that some vehicles are set to read slightly higher than they really are - as a safety thing.
¯\_(ツ)_/¯