How-To for Users
You can subscribe to a calendar generated by ical-relay, so you always stay up to date with changes.
You can copy the iCal Link by clicking the link in the navbar when viewing a calendar.
This Link can be used with most Calendar Applications.
Microsoft Outlook Web
Follow the Microsoft Documented Process here
Microsoft Office Outlook (Desktop)
Follow the Microsoft Documented Process here
Google Calendar
Follow the Google Help Process here
Apple iOS
Follow the iPhone Documentation here