Working holiday visa close to the age limit

I'd like to apply for the working holiday visa as a UK citizen, but I have a few problems:

1. I turn 31 on 9th November
2. The earliest appointment at the embassy is 4th November
3. I am travelling abroad on the 6th November
4. I live in an area that is not covered by the Edinburgh embassy (I'm in Northern England, but not one of the listed counties)

If I attend the interview, I would not be able to hand my passport over since I need it for travelling; I can apply once I'm back, as I'll be gone for 3 weeks.

I was hoping they'd be able to either expedite the process (i.e. give my passport back the next day), but I think that's unlikely. I was also thinking about attending the interview, but not handing my passport over until 3 weeks later, but I assume I would just get rejected and would have to reapply, at which point it is too late. Or, I was thinking before my 31st birthday, I could book an interview, and then attend it once I am back, but I think the age limit is from when the interview takes place (or visa is issued), rather than the date the interview was booked.

I was also thinking if I could apply via the embassy in Hong Kong, but it seems they wouldn't accept applications from non-residents there.

Do I have any options?