I would not worry about that too much. As you have no idea how it was driven or what they have been doing, car could have been turned on & systems running (V2L) while being valeted. What is the long term figure?
More important is has it been serviced as it should have been.
So should have had one service this year. As it is 24 months or 20K miles, which ever is 1st from date of registration.