Hi Xiuyun Lian,
thanks for your reply, but... there are different pieces of information from different Microsoft sources.
First of all, the extract from the Microsoft Customer Agreement related to the Cloud Service Provider programme:
MCA extract
‘f. Restrictions. Except as expressly permitted in this agreement or product documentation, Customer will not (and is not licensed to):
[...]
(v) upgrade or downgrade parts of a product at different times;’
Microsoft Learn
https://learn.microsoft.com/en-us/partner-center/customers/csp-on-premises-software
In a note field
‘In the CSP, we fulfil downgrade rights for the previous versions.’
and last but not least,
your statement
‘I can confirm that Windows Server licences purchased through the CSP come with downgrade rights, which means you can switch between different versions such as 2022, 2019 and 2016.’
Conclusion
Unfortunately, there is no clear evidence in Microsoft's licence terms.
There is a reference to lower editions, but no mention of downgrading.
And from my point of view, the topic should be further subdivided into
What are the options for downgrading?
Up to which version of Windows Server is deployment done via the Microsoft Admin Center?
Question
What should we recommend to our customers in connection with Windows Server licensing with CSP when they ask us about downgrading?
Kind Regards
Olli Leckebusch