SAT registration "Waiting for test center assignment"

Hi guys, I just tried to register for the June SAT subject tests and the status says that my registration is incomplete and that I am “Waiting for test center assignment”. Does this mean that I will be able to take the test and that I’m just waiting to be assigned a test center or that I may not be able to take the test? Thanks.

Once you finish registering, you should be able to print out your ticket. Were all the seats taken at your first choice test center? Maybe you should select an alternative test sight just to be safe.

I have to give SAT subject tests in June too.In my city all the centres were full.I chose the ideal test centre now it says waiting for test centre assignment.How do I choose an alternative centre?