@St_Rev I've been playing around on a test account, trying to post a link that once triggered a shadowban I now get thispic.twitter.com/a6uyfggZhi
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
Hm. Suggests brigading, then, or some kind of cumulative "black mark" filter.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.