Microsoft has notified CCS that Skype for Business is undergoing maintenance. on July 17th between 4pm and 6pm. Interruption in service is expected. They have supplied the following description:
During this time, users will experience limited functionality and will be unable to perform actions that change the state of the user (create new group, create new meetings, changing presence). However, messaging/calling should still work and the ability to join previously activated meetings should not be impacted. The expected time of impact will be 60 minutes or less.
For more information please contact the CCS Help Centre at x58888 or email firstname.lastname@example.org
or visit http://www.uoguelph.ca/ccs/ccs-help