Luftwaffe Flak Training

My grandfather was conscripted into a Luftwaffe ground unit (3./Flak Ers.Abt. 26) in September of 1940. He trained in Barth, Germany. From my research as well as some old family photo's I'm assuming that he was with a Liechte Flak Abteilung. He was stationed in Paris, France. His final unit Flak Regiment 59 surrendered in March of '45.
Although any pertinent history of his original unit is lost, I was wondering if anyone had any info on the length of training time for a Flak Unit?