rajibsam said:
The nomination letter doesn't specify any time frame in which it has to be accepted. From where did you get 30 day limit?
8.
AFTER NOMINATION
If your application is successful, OINP will enter the details of your nomination into CIC’s Express Entry system and you will receive a notification of your nomination through your MyCIC account. This notification will explain the next steps for accepting or refusing the nomination.
1. After OINP adds your nomination information to your Express Entry profile,
you will have 30 days to accept the nomination in the Express Entry system. With the additional 600 points awarded for a nomination, you will receive an Invitation to Apply for permanent residency from CIC through your MyCIC account.
2. Once you receive an Invitation to Apply from CIC, you will have 60 days to submit your application for permanent residency to CIC.
Its all there in the application guide (page 28)