Here's Riot Masima with more info:
We have discovered a high impacting bug on the PBE, overnight testing has confirmed the issue is pretty severe and a fix has been identified and is in progress to be implemented.
This does unfortunately mean we are forced to delay the 4.7 deploy by 24 hours."
Good news everyone - Server maintenance for our next patch, Patch 4.7, has been scheduled!
Here's 2changz with the NA version of the maintenance announcement:
"On 05/7/2014, starting at 01:30 AM PST, ranked queues will be disabled in preparation for patch 4.7. At 03:00 PST, the servers will be shut down and all games currently in progress will end in a draw and stats will not be recorded. We estimate the battlegrounds will be unavailable for 6 hours."Here's a collection of the patch 4.7 maintenance threads for each server:
I'll keep you updated as more information on what the patch contains and patch notes become available. While the latest PBE content is usually a good indicator of what's to come, please remember that it is tentative and not everything may make it to live.