Hello, @Flavius Butnariu !
Where can I find a Microsoft published image for AVD with Microsoft 365?
This was more difficult to track down than I thought it would be. I ultimately reached out to the Azure Virtual Desktop group and confirmed that the Office 365 image you found is the AVD image that is published by Microsoft (no other options for update channel are listed):
It looks like there are some configuration values for Monthly Enterprise Channel on the Microsoft 365 Apps side of things for a cloud deployment which might give you what you are after but you would want to follow up with Microsoft 365 Apps as they would be able to confirm the correct workflow:
https://techcommunity.microsoft.com/t5/microsoft-365/ct-p/microsoft365
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