Ray, I think it could be 1 true hour.
The topic could announced or posted at PST 11:59am and you have to have everything posted by 1pm. you’d have to clear your schedule or find a way to make it work, but you commit to a slot finite timeslot, or even just the first 15min, then post, and done. 1 true hour gives some urgency to it, and you don’t get spoiled seeing everyone’s submissions spread out over 2 weeks.