Misunderstanding in draughts moves notation

Hi, today I noticed one strange thing: scan found mate in 1 where isn't mate in 1!

Detalis in my study:

EDIT: Scan changed his eval to #7. But I'll found another position, where scan is confused.

@root3 I have an impression that Scan shows the distance to some stored tablebase position which can be reached by force, and only afterwards it corrects the amount of moves if a position is winning for one side.