My husband and I will edge for hours...actually all weekend but we do take little sleep breaks. I would say the longest I have personally gone was 10 hours. The only break was bathroom breaks, but they don't count, lol!!
Probably closer to the five hour mark actually, but that was back when my mom was gone for like eight hours a day too.
Those were some damn fun days, I used to play with my toys so much I'd wind up passing out as soon as I finished the cleanup. x'D