The new URLs provide events and work as expected. 

Feeds enabled after November 2016 (from Core or while logged into other “ON” products) already use the new encryption method. Feeds enabled prior to November 2016 while logged into the ON products will need to be recreated and added to external applications.

As of August 9, 2017 feeds from onMessage public calendars also generate URLs in the new format. 

Please encourage parents, students, and staff to check their calendar feeds at the beginning of this school year. If their RSS feeds no longer show events from "ON," they are probably using a feed with the old format. To fix these, they should recreate the RSS feeds from the "ON" calendars (including your School Website public website) and pull the new feeds (with Zs) into their other applications (such as a smartphone calendar or Google Calendar).

Please note, users must grab the new feeds from the calendars. Changing the "Q" in an old URL to "Z" will not correctly update the URL.