Fully resolved. Our on-call team identified a temporary webhooks issue that caused elevated requests sent to users between 4/27 ~19:00 UTC to 4/28 ~3:30 UTC and between 4/28 ~10:50 UTC - ~11:30 UTC with temporary outages between these two spikes. Users were NOT charged for these extra request. Long term measures have been put in place to prevent this from happening again in the future! All functionality has been restored and webhooks are back up as normal.