Technically the reward pool runs off a thirty day average vs daily (I just didn't want to add that complexity into the FAQ). This latest hf, the pool was not reset, thankfully, since that would've needed a month to refill like it did for hd 17/18.
What happened to raise the payouts was that all the votes that had already been cast carried far more wait after the change, even though we had 40 votes a day at the time. So every vote applied more "money".
Posts made after the hf were than rather back to normal since there were less votes to go around and many peoples vote power dropped due to votes costing more power.
At least, this is my best guess on that.