The rumor also says that there is a G48 (what happened to G44, G46 and G47?) which includes the G43x 10rd mag, and a 4" barrel. I guess we'll find out for sure, maybe, partially? on 1/3/2019.
I don’t know what the 44 or 47 are, but the Glock 46 was a rotating barrel lock up model that was entered in to a German police pistol trial.