September 21, 2023 - Here's the most recently updated timeline.
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On March 23, we announced that we would be enabling a transport enforcement system in Exchange Onlin...
Updated Sep 21, 2023
Version 6.0
Blog Post
BalakrishnaG, you can find details of our roadmap at Exchange Server Roadmap Update - Microsoft Community Hub.
Deleted, yes for all versions mentioned above, we are targeting the specific configuration of OnPremises inbound connector in a hybrid configuration. We will post future announcements when we move beyond this configuration.
esczerwin2021, Currently, we're targeting servers that are out of support. When we move to servers that are out of date (later this year), we'll announce the minimum compliant build requirements. The minimum compliant build requirements will be determine using a number of variables, but the last thing we want to do is make it difficult for customers (so we won't block your email if you haven't installed an update in 30 days, etc.).