IOS7 - when can we build/upload and what changes are required for our Corona apps

I’m a bit time poor but getting close to finishing my first app.  With IOS 7 coming up can I ask:

a) Will there be an blog announcement when Corona is “ready/tested” for IOS7?  When is this likely to be?    (perhaps I should be testing now, but my question is more around when CoronaLab’s will give their thumbs up to being able to build an IOS7 release and upload to the app store.  Wondering if this is like: now?, shortly before release?, after the IOS 7 release itself? - haven’t been through an IOS upgrade since I’ve been using Corona)

b) Are there any changes absolutely required to my working IOS6 corona app that will have to be made for IOS7 (just a heads up would be great)

c) Any changes to Icon/Launch images required for IOS7, either bundled with the app or on iTunes Connect do you know?  Or can we just run with existing images & this should work?