First, Facebook sets a posting quota of 200 items per hour per user. Now, because not everyone spends the same amount of time on Facebook, it aggregates its quota based on the number of active users using a particular Application. So, if there are 1,000 people using PopItUp, then PopItUp's hourly quota is 1,000 users X 200 items = 200,000 items per hour. So in other words, the more consultants are using POP, the more pictures we can post every hour. And we post as many of your items as we can within that quota. Also, because not all consultants are on Facebook making requests at the exact same time, you are able to "borrow" quota from other consultants, and POP allows consultants to post up to 750 items per hour.
If the POP system is experiencing heavy traffic, with many consultants requesting actions and using up their own allotment of Facebook quota, the system may slow to comply with Facebook's quota restrictions. Please watch the System Status to be aware of peak posting times, which will help you avoid heavy traffic times when the Facebook quota is being used up, and the system may be slowing to not overreach the Facebook quota.