Last night Microsoft announced and published the Agent Opt In/Out feature to Skype for Business Online.
This update allows Admins to grant Call Queue Agents an ability to Opt In and Out from taking calls from a particular Queue at will.
For all newly created Call Queues, Agent Opt In/Out option will be enabled by default. For pre-existing Call Queues, Admins will need to enable this feature manually.
How to enable Agent Opt Out (Admin) First login to the Office 365 Admin panel Link