Why is our ChartMill app getting 403 repsonses since somewhere in July, until then it worked fine for more then a year?



I built an app called ChartMill (on a twitter account with the same name).
Its purpose was to tweet digests (approx 30 a day) from www.chartmill.com
It worked very fine for over a year and a half.
But today I noticed it’s been receiving almost solely 403 repsonses since the end of July.
I didn’t change any code in the app (I didn’t even rebuild it).

What happened?
Please help.

Kind Regard


probably has something to do with https://dev.twitter.com/docs/security/using-ssl
but then again the app already transports over https