I have tweaked some things Cloudflare side to try and prevent this from happening in the future. This won't help if you're stuck with the issue currently though, you will need to clear your browser/device cache.

A couple of users reported not seeing new posts and/or notification since yesterday evening. We quickly found that clearing your browser cache fixes the issue.

Nothing has changed our side recently and my current theory is that Cloudflare (our CDN/DDoS provider) was returning the wrong Cache-Control headers for a period of time yesterday causing browsers not not fetch new updates.

If you clear your cache (or didn't visit the site yesterday evening) everything seems to be working correctly. Will continue to investigate why this is the issue.