Sometime bunnies can get in the habit of peeing outside their box, and it sounds like he is also in his sassy teenage years, even with the neuter.
I had good luck with Moose with positive reinforcement training a long with adding an additional litter box in the area that he would usually pee around. If he has a very large space, you might even want to add two extras.
Basically it involved leading him to his box with a treat periodically (like taking “potty breaks”) during play time, and then rewarding him for jumping in the box (use either a clicker or “good boy!” to let him know he did the right thing before giving the treat). Then giving him an extra pellet if he actually peed. He picked up on it super quickly, and it then became a game where he would jump in the box, and look at me expectantly for his pellet. I would much rather interact this way than follow him around cleaning up pee!
Definitely try to pre-empt him, as Wick says… the second you see him even thinking about it (usually backing up into a corner and lifting that tail) lead him to the box.
You will need to watch him like a hawk at first, and see if you can pick up on when he pees. Moose would always pee after meals, so I knew to make him take a “potty break” after meals.
It also helps to make the litter box very appealing with lots of fresh hay and soft bedding.
It’s funny that you say “despite being a Netherland”.. in my experience they are the most feisty!
There is also a slight chance that his neuter was incomplete… If it’s been longer than 2 months since his neuter and he’s still acting hormonal, might be worth asking your vet about.
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The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.