If you are applying in Japan, the application process is completely different than if you are applying in the US... and you don't send anything to the UK because you submit your documents in person in either Osaka or Tokyo.
For applications made in Japan:
- apply online
- book an in-person appointment at an application centre (Osaka or Tokyo), where you submit your application documents in person and give biometrics
- you wait for the visa to be processed (in Manila), and then either have it couriered back to you (JPY 1,980) or you can arrange to collect it in person.
Current settlement visa
processing times for Osaka, Japan:
50% in 3 working days
66% in 5 working days
66% in 10 working days
66% in 15 working days
100% in 30 working days
Current settlement visa
processing times for Tokyo, Japan:
11% in 2 working days
33% in 3 working days
50% in 5 working days
55% in 10 working days
66% in 15 working days
100% in 30 working days
If you want, you can pay JPY 54,000 for priority service to get your visa processed in 10 working days (
http://www.vfsglobal.co.uk/Japan/user_pay_services.html)
For applications in the US:
- apply online, book biometrics and pay for the visa
- attend biometrics at a local USCIS centre (run by US immigration)
- mail your passport and documents to the UK
- wait for the visa to be processed and mailed back to you in the US
Current settlement visa processing times for the US:
The UKVI site says 100% in 15 working days for Sept 2014, but from recent experience here on UK-Y, priority applications have been taking around 3 weeks and non-priority 2-3 months.