One quick question:

 

Will a Paypal account showing your address in English be acceptable as proof of address when renewing a British passport?  I would have thought yes as your Thai debit card is linked to your Thai address.

 

Alternatively, I can always order a Thai bank statement.

A Visa outfit that can do the job for you says 

You must supply something in English that confirms your Thailand name and address like a UK bank statement, pension statement, home rental agreement or Thai driving licence 

The Paypal idea sounds OK but for me driving licence would be easier. 

I used my annual tax statement which shows my Thai address in English.

Sent from my X98 Plus II (C2D6) using Thailand Forum - Thaivisa mobile app

Thai driving license only has my address in Thai.

23 minutes ago, NE1 said:

Thai driving license only has my address in Thai.

Mine is in English and Thai, although it is quite new. 

The English one seems to be missing some detail though, ie the Moo number.

go to the UK.gov website it tells you there what is required and acceptable.