PIO applying for OCI

I am a PIO holder, who obtained PIO card in 2005 when I acquired UK citizenship. OCI scheme was not fully operational, so I decided to get a PIO card. Due to sloppiness, I did not apply for OCI until now and am planning to apply for OCI.
The problem is that HCI now is asking for a surrender certificate of Indian passport. I have all my previous Indian passports except the last one which I had submitted for cancellation together with my postal PIO application to HCI. They returned only the PIO card, not the cancelled passport. I have a photocopy of the first page of the passport I sent for cancellation. The passport was valid until 2012. As expected, since it happened several years ago, there is no way HCI will be able to trace the passport and return it to me.
Since it will mean a whole day wasted if I go to HCI in person and since no one is answering phone/e-mail, I want to make sure I have the documents before I go to apply for OCI. Can I apply without a surrender certificate (since I have a PIO card and have travelled several times as a PIO on my UK passport), or do I need to get a notarised affidavit explaining why I can not produce my last passport. Any advice is appreciated.

I think for those who don't have surrender certificate can still apply for OCI as long as they have other documents to support their application. For example, if your passport it lost, you can't get surrender certificate but you can still apply for OCI if you can submit notarised affidavit. Similarly, in your case, if you can submit the photo copies of your passport, your PIO card, birth certificate(from Indian Municipality) and school levaning certificate with your DOB on it, then it makes a strong case. Make sure you take these photocopies(with originals) with you.

Also, on their website they have mentioned what other documents you can submit other than surrender certificate.
"Photocopy of the first page, photo page, last page and other pages having any observations of valid/cancelled Indian passport of parents/grand parents OR copy of Surrender Certificate of Indian passport of self/parents or grandparents OR nativity certificate orbirth certificate from Indian Municipality/Panchayat with stamp/seal OR copy of school certificate / land ownership certificate, (along with other supporting documents) by which eligibility may be reasonably ascertained. "

http://www.hcilondon.in/oci.php