We have reports of users in mainland China (so, yes, behind the China firewall / GFW) having severe timeouts for hours at a time attempting to contact a host outside China, sometimes most of the day. This has been happening for about a week now (as of June 23rd). Previously this was a very rare thing, only a few timeouts scattered over months.
Anyone else seeing anything similar? In troubleshooting I have found that the 2 Cloudflare IPs are 104.16.53.111 and 104.16.51.111. I do not know if these IPs are always the same when doing a DNS lookup or not as I have not been taking note of the IPs that the hostname resolves to. The problem does not seem specific to the hostname(s) but instead to the IPs.