I was an A Splitter, I had 3 summers. First summer after plebe year was 3-4 weeks. 2nd was 3-4 weeks, but I was doing an internship at the same time. 3rd was after I finished 2nd sailing, didn't take a break between ships so I sailed 9 months straight. That summer was almost 2 months. May-July if I recall.
So yeah it's possible to get 3 full summers as an A Splitter, worked out fine for me. Never did anything for indoc because I convinced the commandant I was screwed on seatime, which I probably was.