I used americanpassport.com as referred by delta.com for extra passport pages. I believe it is the same company as visacenter.com. I called the company instead of just filling out the online form. The rep explained the pricing components.

The rush service fee is based on when they schedule an appointment with the consulate not the date you request the passport returned. In my case i requested 7 business days on the return but elected to schedule the consulate appointment in 2 business days so i paid the higher fee. I could have scheduled the appointment for a later date, but decided to play it safe with the earlier date.

To the the op, what day was the consulate appointment? Did you have any choice in the matter?