If it's indeed a "G42" then it makes sense that it might be the smallest in a family of guns in a different caliber. Although I can't imagine why they'd want to make 3 sizes of gun in .380. It would be pretty funny though if the "Glock 40" became a full-sized .380. Maybe rappers would buy those instead.
If the G40 and G41 were Shield/PPS competitors in 9 and .40, respectively, then I could forgive the G42 being an even smaller .380...