You're welcome to try Thread Writer for Bluesky -- a new software snack I wrote. A few friends have been through the setup process and it appears to work. As far as I know it's the first non-manual way to write threads in Bluesky. I call these kinds of things software snacks so they are not confused with bigger apps like FeedLand or Drummer. Go here if you have trouble or just want to report success (very welcome) with a link to the thread you posted.