Prometric — Schedule change one day before USMLE Step 1

Prometric called me one day before my exam (USMLE Step 1, an 8-hour long test) saying that my schedule was changed from 7:30 a.m. to 6:30 a.m. I had been preparing to be ready for the test by one month, and this change of schedule deeply disturbed my performance. I was much more tired than normal. I wish Prometric had advised me about the schedule change at least one month before the exam.