Each campaign checks its feeds on its own schedule, which you set in the Update Frequency box: Try to add a new post every 1 to 1440 Minutes, Hours or Days. New campaigns start at 60 Minutes.
For example, 30 Minutes gives about 48 posts a day and 2 Hours about 12, as long as the feeds have enough new stories. Match the interval to how often your sources publish. See Campaign schedule - frequency, start time and max posts.
Start with 25 free posts — no credit card needed.