Longines le Grande Classique 37mm quartz minute hand interval

Hi, I have a Longines le Grande Classique quartz 37mm MOP with diamond marker, ref L47662877, which I have recently bought. It gives perfect time, but the minute hand strangely jumps every 24s. I expected it to be a more round number. Since this is a discontinued model, I have not seen another or similar piece in a shop to check against, but have checked this on similar smaller size models and the minute hand on all these jumps every 20s.

Does anybody have a 37mm version they can check the minute hand jump interval on? Thanks.