Latest Update :
We’ve postponed the systems upgrade to January 2013. We would share the date and time when we finalize it. We would notify in advance, all users via the Y! Groups notification message on the groups website.
The planned systems upgrade for Yahoo! Groups has been postponed and will not happen as planned on November 18th 2012 evening. The upgrade date would be announced shortly. We would update this post and also notify all users via the groups notification message on the groups website.
Thank you for your support !
– Yahoo! Groups product team