Quality Info record Block for a certain period

Hi

Our requirement is system should not allow to do GR against PO/Schedule line for a certain period.

This we are trying to achieve using Quality Info record- release date  but not working.

Example system should not allow GR upto 25.06.2015 so we given qulity info record release date as 25.06.2015 and Blocked as Total Block.

From26.06.2015 system should allow GRN.when we tried still we are getting blocked error message.

Please suggest.

Regards,

Srihari.M