Noodles..
The message that you get "an information sheet.." means that they need a reconfirmation letter.. You need to respond to either that letter or mail in a letter yourself. If the NVC does not hear back from you within 30 days, they will then go ahead and send out your packet 3.. But you just lose the 30 days.
Your case number has already been created before they sent the info. sheet. If you call them, you will find out the number.
In your case once you enter the INS or NVC case # in the AVM, it will say "an info sheet.." and will not connect you to an operator. You need to call the NVC (same num - 603 334 0700) and enter an invalid case or receipt number, say all zeros and hit 0 to connect you to a live operator.
So hit 2-2-3-2 262 (for BMB) 1 0000000000 1 0 for an operator !
HTH.