Hi @Boris P ,
Can a user from the GUI modify the work week / hours / location for a specific calendar, which is not his profile calendar? More specifically, for a Shared Mailbox calendar.
Seems like no. I tried testing in my lab tenant and also failed to set this for a shared mailbox calendar from OWA > open another mailbox. The settings are all grayed out with the message below:
Is there a CLI way of affecting those new settings? (Different locations and work hours for each day).
I am afraid no, at present, there's no CLI way or other options available for administrators to manage the new Working Hours and Location settings for a mailbox.
As you have mentioned, this new setup experience is currently only available to end-users in Outlook for the web and the New Outlook for Windows. See this official document. While for administrators, based on what I've learnt, no options have been provided for administrators to control this feature for users.
Given this, I've provided your feedback through the official feedback portal. The link would be left below so that both you and other users who see this thread can vote it up or comment there. Hopefully this administrator functionality can be added soon.
https://feedbackportal.microsoft.com/feedback/idea/efa36997-472c-ee11-a81c-6045bd8534ad
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