I got my AINP nomination from December 2014. I have applied through EE. I have also emailed AINP about the nomination confirmation. I got this reply:
"
You have not been nominated by the province for the purpose of Express Entry. As a provincial nominee, you should proceed and apply for permanent residence as per the instructions provided to you with the AINP nomination (prior to the six-month expiry date).
The AINP will not be providing additional confirmation of being nominated.
"
So, nominations issued with previous system can't claim those 600 points