Hi everyone,
I am in the same boat. Had Oath Ceremony on Nov 9 and my tickets to India were already booked for December 16th.
During the Oath, the agent said he cannot expedite certificate unless travel is less than 3 weeks away. So, the certificate came by mail on November 18th. Applied to passport on same day and via express process got it on November 24th. You can even ask them to give the passport earlier and explain you want it in 1 or 2 business days since its urgent. On the 24th itself (yesterday)I applied for passport surrender and entry visa. I will let you all know when I get the entry visa.
You can call BLS as soon as you know expected date of passport and they will give you a shipping label to mail your applications to BLS for the next day after you get your passport. I am in Montreal, so I got the shipping label for Ottawa. BLS uses Purolator for shipping. You pay for both sending and receiving documents.
I called BLS a few times since I had questions about documents etc.