after you remove your flume as well as your gossip database (leaving you with a secret only) You might need to hop in a room, pub or wifi-link with someone that has your data, which means re-subbing to that data-source.

@moid is pretty right. there are a good bunch of sources in your network with blobs, so you can harmlessly remove some old ones. when you end up re-visiting a view in Patchwork or Patchbay that contains a refference to that blob, your client will just re-download it.