How to travel abroad when passport is with Home Office

Hi,
I have applied for Tier 1 visa last month and my passport is with the Home Office along with the visa application. The processing time is around 8-10 weeks for Tier 1 visa. I am an Indian national workiing in UK with work permit.
My query was that:
If I have to travel back to India urgently what should I do? (since my passport is with the Home Office).
[ I dont want to withdraw my Tier 1 application and my wife can collect my passport on my behalf in UK after I leave the country.]

I have heard that some embassies can issue concurrent passports in such cases. But what is the provision for urgent travel by Indians inside UK to any other country? Does the Indian embassy in UK issue any such concurrent passports or travel documents which can be used instead of passport to exit UK only?
Please note that I just want to travel back to India when I have to. I do not want to re-enter UK with the same document.

Any help is highly appreciated.
I am sure many people must have faced this situation.
Regards
LG

duplicate pos