Thanks for the encouragement everyone. @Moegie84, congratulations on getting in! Nice work! And thank you very much for the tip too, I appreciate it very much, but it looks like I’m definitively too late. I had my sister over yesterday and we had a great time playing games and eating pizza, and I only saw your message just now, the next morning. I don’t see a way in anymore.
While I’ve resigned and accepted that there’s no JLPT for me this summer, I’m still somewhat in disbelief over the amateurism of Leiden U’s work. This concerns people’s futures, you know? You’d think the oldest and possibly most renowned university in the country would take things more seriously. What a disgrace.
Well, I’d be remiss to let this discourage me from working toward the future I want, so time to grab a drink and hit the books. And it does give me a sense of comfort to be able to read everyone’s nice comments here. I’ll be rooting for everyone without regrets once July comes around. 
I finished another study at the UCD and will be in Dublin in the first week of december for the conferring ceremony… and from what i’ve read on the UCD website, the JLPT exams are also held in the first week of december. If i manage to study up to level N4, I may take a shot at the N4 exam at UCD!

The structure of japanese sentences and grammar is quite a challenge because it differs so much with English (or other north-west european language). I’m sure i’ll manage eventually! Going strong with WaniKani, Genki 1 and BunPro 

I completely agree. I, too, find that the fundamentally different structures make Japanese hard to learn. But when I see that through hard work and passion it does gradually start sticking, it feels very motivating.

