Found it on the Camo Workshop website ...
One unit playing piece represents one vehicle or gun, or an infantry squad (section of up to 19 men in winSPWW2 and 13 men in WinSPMBT) or a section of 1 to 4 support weapons.
One game hexagon represents 50 yards/metres of terrain. One game move (player 1 turn plus player 2 turn) represents roughly 3 minutes of 'real time'.
This should probably be pointed out in the
Features column of the Shrapnel page as well, I'd suggest.