Re long term Visa...this is what the folks say on VFS site
A Long term entry visa is issued to people of Indian origin only and hence appropriate documentation is required to substantiate Indian origin
e.g copy of surrender certificate of Indian passport or any document issued in the name of the applicant by the Government of India.
which in turn implies, you need to surrender first.
Even if you put in say your PAN card or some voter id card which was issued by the Govt along with the receipt of passport surrender, someone having a bad day can delay your case...a risk not worth taking in my opinion
For your own satisfaction, you should call up the VFS in London and ask if they'll accept such a Visa application along with a surrender application....
here's the link from which i pasted the above information:
http://in.vfsglobal.co.uk/longterm.html
As for putting in an OCI application soon after a Visa stamping, I don't see that as an issue...Indian authorities say there is no emergency service for OCI and
"
If you are travelling in the near future and have an emergency, please apply for visa.
"
doesn't matter how soon or later you apply for the same. If you are still unsure, just ask the folks directly in Bangalore and even after that if you don't feel comfortable then apply when back in London. Doesn't change anything.
In nutshell, the more we complicate things, the worse it'll become ....all the aspects you raised are grey areas where those folks behind the counter have the authority to apply their own judgement...we all know what happens when that happens
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