Hi @tilsammans , @Scott is right, the date header corresponds to the date when the CDN server cached the content.
BUT (and this is a big but) @Scott, a “good” CDN would send the current date. You can read here Forums | AWS re:Post why it’s problematic regarding client caching (due to this, browsers tend to not use local cache correctly, which increases TTFB). From my tests, Firebase Hosting and Stackpath return the current Date while Cloudfront and Netlify return the cached Date, which increase TTFB and bandwidth for assets like Javascript and images.
Combined with the fact that Netlify use the same CDN cache from free to business users, it reduces the competitivity of Netlify for Pro and Business users.
So @Scott I would love if we can have a discussion about Netlify changing this behavior regarding the returned date (maybe with a configuration field in netlify.toml, for backward compatibility) in order to reduce TTFB and bandwidth 