Why the 'Expires' header value is of yesterday?


With the Pro version, I’m getting familiar with CloudFlare cache, and I’m testing a directory of my website (* myserver.com/dir/*) with a Page Rule with the following settings:

  • Browser Cache TTL: a day
  • Always Online: On
  • Cache Level: Cache Everything
  • Edge Cache TTL: a month

I’ve just tested with ‘curl’ the cache headers of one of my webpages, which I tested yesterday with ‘curl’ with my Linux laptop:

  • Cache-Control: max-age=86400
  • Expires: Wed, 11 Nov 2020 11:38:42 GMT
  • Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
  • CF-Cache-Status: HIT
  • Age: 87441

I do not understand why the ‘Expires’ value is of yesterday. According to Mozilla (https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Expires), this means that the response “is considered stale”.

Any tip to understand this is welcome. Thank you.