Worldwide Income in Japan

Hi there, I'm looking for some advice / confirmation on the below.

• I am a UK Citizen and former UK tax-payer, long-term resident.
• I will be living in Japan for just under one year, I have a permanent address.
• I have a working holiday visa for Japan, which allows me up to one year in Japan.
• I am earning money internationally via freelance, remote work.
• I do not have a Japanese bank account (if relevant).

I am not sure whether I should be paying tax in the UK or in Japan. It seems as though I miss the cut-off for being a Japan Tax Resident, because I am living in Japan for under one year. Is this right in my case? It seems odd to me that this working holiday visa scheme exists if I do not actually work/pay any tax in Japan!

Thanks in advance.