If you are talking about the "Permit to Report" and all of the R-day information, all of that comes in mid-late May.
Your appointment package (which you will have before then) should have most of the forms you need to send before that (immunization, fingerprints, etc), as well as the deadline for the remainder of your $3k deposit.
You will also get a parking pass for the Sunday Open House (Chase Hall tour) and dinner in the wardroom, which gives you a chance to meet the other people in your company or athletic team before the next morning.
You will be assigned to a specific company (Alfa - Hotel) and that will determine your report time: 0700 for A/B/C, 0740 for D/E/F, and 0820 for G/H.
But I would start looking into hotel reservations now. Hotels in New London fill up very quickly for R-day and the days immediately before/after.