Twitter confirmed their bug is now fixed: https://api.twitterstat.us/incidents/vz25tls0vk4d.
Thanks again for your patience

We’re currently impacted by a global API Twitter outage, as you can read here https://api.twitterstat.us/incidents/vz25tls0vk4d

Unfortunately, this means that we cannot synchronize your inbox or publish some tweets, randomly.

We apologize for this issue which is outside of our control