Coexistence mode changed for no reason

[Lisa Stebbins]

For some unknown reason, we found that our TEAMS was set for Island Mode instead of Teams Only. I switched our tenant's mode from Islands mode to Skype Only over a year ago and then, from there, switched it from Skype Only to Teams Only in July 2019. Now, all of a sudden, the mode is mysteriously back on Islands mode with no explanation. Is anyone else experiencing this? Is there a log that shows who did what when so we can make sure it doesn't happen again? Is it possible that MS did something in the midst of all the updating that's happening after Ignite? I really need some insight and ideas ASAP. I am going to be held accountable to something I didn't do since I am the TEAMS Admin.

[#2]

It should not have changed itself, I have not heard of this before but hard to say that it couldn't have happened.

You can go into the audit log search in the compliance center and see if you can find anything under the "Changed organization Setting" logged action. Not sure if this picks up Teams upgrade mode changes but worth a shot.

[#3]

Hi,

Just wanted to mention that we did have the exact same scenario. Teams suddenly out of nowhere changed to Island mode, from being Teams only for more then 1y.
Audit doesnt list any changes being made for organization either.