A header event of a Publish on multicast would stop the channel being burdened with data, then subscribers can choose to filter or fetch at their own convenience.

A header would allow subscribers some interesting use cases…

- local mode: prioritise local (subnet) content, defer external

- p2p mode: allow those with header to fetch from your notedeck’s sent queue (as a pseudo relay). Stealth mode, or a data sync if you hand off to a tcp port.

Be great for mesh networks.