Website still facing this caching issue.
Although the content on the server has changed, the server sometimes returns 304 Not modified, with an old etag value, and old content.
The remote address is still the same for the two requests (52.154.67.183:443).
The chances that you miss an update due to this are very high.
Oh and while we are at it… is it really necessary for the main banner to cover the whole viewport?