@ Kopper. That's exactly what the lady said - it's not mandatory. There is a chance that you might face some questions at the airport immigration counter if the appearance of your daughter has changed. It's probably worth the £18 hassle to be safe but I have travelled in Aug 2013 with old & new ...
Things have changed at HCI. They don't give tokens for OCI/PIO anymore. You have to take an appointment online before going to submit the documents. I had a 12noon appointment today to submit forms to transfer mu kids OCIs to their new passports. Got to the HCI at 11:40am, was allowed in quickly as ...
So, what happened here? The "grace period" mentioned in the last post should have applied & you won't need to pay a fine I think. Do post a reply as to what experience you had.