Yeah it's over time. I might masturbate for 30 minutes and then stop. Then I might start up again a couple of hours later and do another 30 minutes - sometimes an hour, depending on my "about to cum" status. If when I start masturbating the sensation of cumming comes quicker, I won't go an hour but maybe 15-30 minutes.
The longest edging session I had was about 7.5 hrs - with short rest periods for snacks and restroom breaks. That orgasm was CRAZY!
Simba