The Iconfactory, State of the Twitterverse :
News quickly spread on Twitter and Mastodon that a wide range of third party apps like Twitterrific, Tweetbot, Echofon, and many others had been disabled. Strangely, Twitterrific for macOS continues to work normally. We cannot say for certain why some clients are unaffected, but it seems possible that there is a new (seemingly unstated and unannounced) policy that is only being applied to apps with large numbers of users.
Can't wait for the Chirp Developer Conference.