Renew Passport in UK or while visiting home?

My husband and I are living in the UK but visiting home in Canada in 3 weeks (June 6). Husband realized the potential dilemma of his passport expiring in July... Should we get a 24 hr renewal in London or is it possible to wait til we're in Canada and get a 24 hr one there?
I have a student visa, and he has a student dependent visa.
Thanks!

Just curious what you did in the end? I'm in the same position, and having waited too long before my trip home this summer (my passport expires while I'm in Canada), I can't get it renewed in the normal way in the UK -- 15 days is too late. Not to mention that getting it renewed in Canada, even paying for the rush service, costs no more than getting it done in the UK. And way easier if I can use the new guarantor rules.

When I finally went through the paperwork yesterday and realised HOW MUCH crap I have to fill out to get a passport renewed here -- plus giving them essentially every piece of ID I need for my visit home with the chance that it won't come back to me before I leave (DL, current passport, birth certificate), I had half a mind to just send them back my old passport and tell them to keep it for good!

(I have dual citizenship in the Netherlands which is probably what I'll be using to fly home with as the flight ends in the USA. When I went in to the local Dutch gov't office to renew my Dutch passport a couple of years ago when I was living there, I literally walked in, handed them my old passport and my money and the new one was ready to pick up a week later. Not sure why the Canadian passport process has to be so complicated or take so long....)

Anyway, rant over... be interested to hear others' experiences in renewing passports when they're home visiting -- how long it took, what application they had to use, etc.

Just wondering what the outcome was? Did you end up getting your new passport done when you were back in Canada?

Also, I have a visa-related question (i.e. what happens to a valid visa stickered into an invalid passport) but I'm guessing that since you're a Dutch citizen as well, you didn't require a UK visa in the first case.

Thanks!