Thank you, that was one of my questions. What about connections to the server IP (152.199.4.33) with a different SNI?
The ajax.aspnetcdn.com server was previously blocked between December 1 and December 13, 2021. At that time, the block was of the entire server IP address (which was then 152.199.19.160), not only a single domain. The block only affected certain ISPs in Moscow and Saint Petersburg; it sounds like it is more general now.