Thanks for posting in the Cloudflare Community and sorry for the delay. We are investigating this issue internally. Do you mind submitting a support ticket and providing the ticket # here once you’ve done so?
We will group you in with an internal tracker and update you on our progress/resolution in the ticket. If you already submitted a ticket, go ahead and provide the # here and we’ll jump to it.
If anyone else is reading this thread, go ahead and do the same as suggested above. Thank you!
Also, I have now an answer from Yandex (there is a TYPO in my ticket. Not “for Yandex”, but “from Yandex”)
Here is the translation:
We have checked the IP address you’ve mentioned, and at first glance, there is no any error with it. We don’t have any list of all IP addresses, which we could give to webmasters or hosting providers. That is because we utilize many IP addresses, and they are changing constantly. Moreover, differnet services of Yandex.ru can use different IPs. We recommend that you check our IPs with User-Agent + Reverse DNS lookup, as it’s described on our Help page Как проверить, что робот принадлежит Яндексу - Вебмастер. Справка.
We see, that this IP is fully complied with our documentation, as well as the other IPs. Thank you for the notice, we will try to keep in mind your case with Cloudflare. Could you talk to Cloudflare please also? What is the reason for that blocking action. It could help us understand faster is it required to change anything on our side.