@Eventually I was in your exact position last year. I had passed AUD, BEC and REG after multiple tries which left our good buddy FAR. I had three testing windows to pass. The first attempt was a 65, the second resulted in a 69 and the third and FINAL window I scored a 75. My AUD was set to expire on January 31, 2013 and I sat for FAR on January 28, 2013.
If I were you I would schedule FAR around May 28th which is at the end of the next testing window but enough time before the expiration of your AUD score . This would give you a good 11-12 weeks to prepare. The volume and complexity of FAR is mindboggling so scheduling as late as possible will give you maximum study time.
No joking you need to devote and I mean devote yourself to passing this last section. I was studying for FAR during Thanksgiving and Christmas of 2012. I went to my parent's house for Christmas and that was it. No going out with friends, no birthday parties, etc.
You have just passed REG and congratulations. I hope you got to celebrate last night but the celebration should be over today and you should immediately start studying for FAR.
Best wishes and good luck!
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