This add-on is currently at version 0.x, which implies that it is not yet "stable" (meaning how it works and what it does are not yet finalized). You can see updates and changes here -> https://addons.mozilla.org/en-US/firefox/addon/awesome-rss/versions/

The last few releases were on the 22nd, 21st, & 17th.

Are you getting updates more frequently than this?