The problem doesn't seem to be Plume, it seems to be twitter. Updates have been wonky for me on Tweetdeck (phone), Plume (Xformer) and Tweetcaster (Xformer)
Twitter can't make a decent native client (or function correctly consistently) so instead of wasting precious research time on fixing their native offerings, they work to make life difficult for third party offerings that give a better experience.