Moving to Japan as a UK national living in Canada

I’m a British citizen, and I’ve lived in Canada for the last 6 years. I’m waiting on my citizenship, but with the unbelievably long processing times at the moment, I won’t have it any time soon.

I want to head out to Japan this winter as I just turned 30 and it feels like my last opportunity to do so. I’m aware that I can’t apply from Canada, so I’ve come back to the UK for the next 4 weeks. Is that going to be enough time to apply and get a visa?

I have to be back in Canada in October, and so it feels like this is going to be my only opportunity to get a visa.

There is a chance I could come back to the UK for a few weeks in November, but I’d rather avoid the time and expense to constantly fly to opposite sides of the globe!

Is it possible to get an appointment and a visa in 4 weeks?

Edit: I’m trying to get a working holiday visa