@KaiRyuuji This is great advice, imo, if you’ve been very serious about hitting N4 by this coming December. You can even make a “deadline date” where you plan to go to a library, take a practice test, let the hushed quiet of the library serve as some test pressure, and see how you measure up without dropping $100 on the official thing. For added spiciness to the test-taking ambiance, if your university has a law school, use one of the carrel desks in their library for your test spot. Guaranteed pressure, especially in December lol.
My advice is to use an N4 study guide of some sort (like JLPT Sensei’s), come up with your plan of attack (15 new vocab per day? 10 new grammar per week?), and treat it officially. You are NOT the only person who missed sign-ups - even I was truly astonished at how quickly they filled up this year! Like concert tickets! It could be worth it to post in the JLPT thread and/or the N4 thread and ask if anyone wants to schedule their mock test at the same time as you, maybe even multiple people will be happy to join as study partners.
Or even if you don’t do any of this, please don’t let this break your focus! Make next year your N3 year, regardless of whether your N4 score was official or not 