The load appears to be just about back to normal. By server count we've almost mostly recovered from the "lost" servers during the event.

https://community.ntppool.org/t/recent-ntp-pool-traffic-increase/18/10

Snapchat released an update to their app yesterday with a fix. They've also added some high capacity servers in some of the affected regions. 👍

More information:
https://news.ntppool.org/2016/12/load/
https://community.ntppool.org/t/recent-ntp-pool-traffic-increase/18

The trouble in some regions of the world appears to be caused by the Snapchat application:

http://mailman.nanog.org/pipermail/nanog/2016-December/089588.html

We've tried reaching out to them.

Since around last Tuesday the NTP servers in some countries (or so it appears) have seen massively increased load. We believe it's a vendor not using the vendor system and haven't yet been able to identify who it is. It seems to mostly be affecting the United States, United Kingdom, Australia and New Zealand.

If you are running an NTP server, your service is greatly appreciated. If your server is seeing more queries than you can handle, please consider lowering the "net speed" in the server preferences rather than removing the server altogether.

If your server can handle more NTP queries than it currently gets, please consider increasing the same setting.