not-shooting for a few days doest really make much difference. Not shooting for 24 hours prior to an event helps, but after 24 hours the tanks are full and production backs off..
The best way by far to increase volume is to not have a "quickie" - rather, try to wank for two or three hours and back off before you shoot every time.
ALso.. this is tricky to describe so bear with me - to increse the "squirt" rather than dribble, whn you are about to shoot, try not to tense up too soon. If you clench those muscles before you shoot there's no pressure behind the stream. The muscles you squeeze to try to not-pee. Visualise a piston in a cylinder - to get the longest squirt you want to start with the piston held right back and not slam it up the cylinder until the cylinder is charged! Does that make sense? Can anyone explain it better?