That's a complicated question. Getting stronger will definitely help gymnastics in general - but it isn't just a question of getting stronger. One also has to translate strength into technique. Different kids also build strength in different areas at different rates. The conditioning program changes results, too - at a given point in the season, the coaches may design conditioning to target different skills/motions in different ways.
So the answer is - more strength can't hurt. Hard to say when or how it will show. Maybe months rather than weeks, I'd think.