The Japan Foundation announced today that the JLPT will be held twice a year from now on in London, starting this July.
http://www.jpf.org.uk/whatson.php#324
This is good news for people in the UK (and possibly countries close by who don't offer exams twice a year).
SOAS hasn't updated its webpages yet, but I'm sure if contacted they will give you the details of how to apply.