I am not sure that there is an AS level, however, I took a similar exam, Russian A level Edexcel and it had 3 exams. I don't think you could split those exams into two (AS and A2), so you have to take them all at once in year 13. I just googled it and yes, Japanese Edexcel A level still exists, but it also has 3 exams and I don't think you can split it. I hope this helps! Also if you are planning to take the exam outside of your college (like I did), don't panic if your exam center doesn't offer this subject. You can bring in your own Japanese tutor (I hired one just for this exam) for the oral exam and the invigilator will just stay in the exam room. For the other 2 papers, you don't even need a Japanese tutor. If you have any extra questions, I am happy to help you!