Even neutered buns can poop-mark sometimes. My Bam had a relapse of pee- and poop-marking more than a year after he’d been neutered, so I had to block off the couch just as I had to do before he was neutered. After a couple of weeks I unblocked the couch again and we’ve had no incidents since, it’s been 2 years now.

But he does poop-mark on the floor next to the gate that separates him from my other bunny, so even a neutered bunny can poop-mark if he feels there is a need. In Bam’s case I think he does it to deter my other rabbit, they are not friends. But buns can of course also mark places that are valuable to them, like the spot where the human often sits or lies. There is no guarantee that neutering stops that completely.

My rookie and I had the same issue. It’s not completely solved. I just put the litterbox on the bed. He went back to using it. Haven’t been able to move it though. And if I’m busy like you and he feels I don’t have time for him he pees directly on a pillow in my bed. Same pillow thankfully. But yeah he makes a statement of you need to make time for me. Rookie is 8 months and neutered as well.