Auto-Archiving for Exchange Online

Agreed that the main issue is that the time we were given was insufficient.

That said, the change itself is also problematic for my org. I'm an admin in one of those orgs that have a well-defined archiving policy, and my team needs the ability to accurately predict when a given item will be moved due to the archive tag that's applied to it. If I create an archive policy tag that says an item gets moved to the archive at 5 years, I expect items that tag is applied to to move to the archive at 5 years. Not 5 years, unless the mailbox needs more space. I find it frustrating that Microsoft believes we want policies to act in a way we did not define them to. 

Larger orgs that have well-defined archiving policies also should have infrastructure in place to do things like monitor mailbox sizes and notify users who exceed a certain threshold. The change itself doesn't solve any problem that my org has, and it generates uncertainty about how the policies that we've defined function in production. 

If given more time, we could incorporate this into our existing archiving strategies. We could change our warning thresholds to be below 90%, so we could keep users under Microsoft's newly defined threshold that breaks our archiving policies if it's breached. But we'd much rather be able to disable this automatic archiving feature altogether.