Did you hear of room lists? What is a room list?
A room list is a collection of room mailboxes. Room lists are specially marked distribution groups that you can also use the same way you use ‘regul...
Updated May 21, 2020
Version 5.0
Blog Post
Jarrad_McMullen Thanks! I've logged a ticket with Microsoft Support (case #29987364), hopefully they treat it with the urgency it deserves!
Also, I completely agree with the second part of your comment. We have thousands of users returning to dozens of offices this week after spending most of the past two years working from home, and health regulations are extremely strict regarding how many staff can occupy a room. This issue makes it very difficult for staff to comply with capacity limits.
Edit: This issue appears to have spread to OWA now, so there goes our workaround! Though on the bright side, this indicates it's an Exchange Online issue, not a desktop client issue. Theoretically should make remediation and resolution simpler.