Today I have identified a possible bug in Cloudflare system. When cf-cache-status is Hit. Some of the static cache resources saying * It appears that the Date header has been changed by an intermediary. and it has an age header present. which is causing resources to become stale immediately.
I’m confused by their claim that the Date header has been changed by an intermediary. The “date:” header is the current time, GMT. I’ve not seen it deviate from the actual time.
I do see that Age is greater than Max-Age, but I don’t think one has an effect on the other (I could be wrong). I also see that Expires = Date + Max-Age.
Currently Cloudflare team has disabled Age: header for my account and things seems to be working nice. But I see this issue for whole bunch of Cloudflare sites. I even have a way to reproduce the error in normal browser window.