No way you are holding the rim at 6'2 with a 17 inch vert.
No one can tell how long it will take it, it's different for anyone else. You should also be doing a strength program with the plyo's, as they aren't that effective without weights ( unless you can already squat 1.5x your bodyweight, but you should still be doing weights anyway). Do VJB bodyweight or novice weights if you have access to weights.