You should be getting your form letter quite soon, that can take about three~four weeks. For a rough estimate, count nine Fridays, but DO NOT BOOK ANYTHING for PIR until you have the official date. Tell his family to be patient, this takes a little time.
His paygrade has nothing to do with the length of boot camp.
Join the Navy moms boot camp group for detailed information:
I put info on your My Page that will help you get started.
Your recruit will send one form letter to the person he chooses to send it to. If you are his wife, then he will send it to you and you will also receive the DEERS package around the same time.
You are within the window to receive The Form Letter, which now arrives 9 to 14 business days after the recruit's arrival at the RTC in most cases, since today was business day 10 since he shipped.
I hope to see you in Boot Camp Moms (and loved ones).