Hey. I am also using the premium version of yoast. I have mailed them. But anyways heres the update.
I got another update from yoast automatically just 10 minutes back. I updated the plugin and everything went back to normal.
I have a blog which i am not using anymore. So i deleted yoast completely on that site. And installed it again. no data was lost. So a big thank you to @pramod.kumar for the heads up.
@Sachin_Alam - yes i do have premium yoast. But due to time difference they take some time to reply. This happened in afternoon in India so i cant expect reply till tonight. And this was urgent issue so i posted in this forum. Frankly generally i find many of my answers very fast on this forum thanks to many people on this forum and especially to @Derek and @GulshanKumar
@Derek - possibly this yoast update affected genesis theme users? are you still using genesis?
The problem thankfully seems to be resolved.