Applied in November, got an email in January, confirming my interview, interview took place at the end of January. I didn't find out the result of the interview until April. Was very formal. Did a short grammar test at the start and then had a 20 minute interview with a panel. I recommend researching a lot before going into the interview and roughly preparing your answers in advance - no question that I received hasn't already been written on glass door. I received an offer if someone dropped out, so not actually an offer. I declined this as i didn't want to be kept waiting

You will be interviewed by a panel of around 3 people. One person was kind of the "bad cop" who would ask tough questions, so be prepared for that. The main interviewer will ask you about your professional and educational background, and be sure to highlight any activities that involve cultural exchange or involvment in the Japanese community, rather than strictly interest in Japan. Another interviewer will try asking you questions in Japanese, but this is usually only bonus points for the interview.