Skype Mac Insider Fast 16.6.328 Issues

We have several users on the insider fast program with Skype for Business, we have been receiving several reports today of users on 16.6.328 having the below issues: 

• Unable to place calls - skype call to internal users rings, called party answers but continues to hear ringing and does not connect the two parties
• Unable to receive calls - client does not ring, receive missed call notification in email.
• Receiving messages - Mac client user is intermittently unabel to receive messages, sneder receives a notification that "This message was not sent to user".  User will receive the message after a quiting and restarting the application.   
  
  • In some cases the receipient will receive the message 30-45 mintues after the message was sent without a client restart. 

Attached screen shot shows the message clients are receiving when attempting to send messages to our Mac users.  We have an open case for this 117041715611371 (open case number is the one shown in screenshot)