Should I waive my grace period?

I just graduated on 5/19. I'm hoping to attend a phd program starting in september. I had to register in abstentia during the spring in order to complete a full time internship. The university automatically indicates zero hours when a person registers this way regardless of the activities. SallieMae now thinks I stopped going to school in December and my grace period is expiring in 10 days. I want to consolidate with a different lender but to do so would require me to waive my grace period and then apply for an economic hardship deferment in order to hold me over until September. Is this a good choice or not?