To subscribe to the calendar:
HTML: 
https://outlook.office365.com/owa/calendar/[email protected]/1670d2cd79444bdbb835be18c48ec5214693188058675234567/calendar.html

ICS:  https://outlook.office365.com/owa/calendar/[email protected]/1670d2cd79444bdbb835be18c48ec5214693188058675234567/calendar.ics