Sony do not usually reply on the forum as it's a user 'support' forum..
Heard nothing official but think we are looking at ten to fourteen days after Japan & the US release, so I guess sometime in early May but that's just my thoughts..
Nothing official but from what I recall reading around the net it seems that the rollout has been done in the US & Japan only so that they can assess if there are any issues before rolling out to the Europe & other countries....
I work in IT and have done for very many years. This type of phased release is not uncommon, I'm sure you'll have heard of alpha and beta programs. This next step is often termed Restricted Access or Resticted Release etc. The idea is to monitor for any bugs or issues further to the testing that are identified by the greater community - however it is a full release and once a specified time or number of users have used the release it is then moved to full release - i.e. when we should get it, which according to some reports I read was 14 ish days after US release.