Testicles do naturally hang, so it sounds like they have descended and he’s ready to be neutered. Unless what you’re saying is they were already descended, but now there is a noticeable difference in how much they are showing un-retracted (ex. they are swollen or something).

Ah then it is probably just his body naturally maturing and him showing his assets, haha. Sometimes he may ‘suck’ them in, so you won’t see them. Neutering is not as necessary for males as spaying is in females, since females have a high risk for uterine cancer. That being said, the accompanying hormones can make some males pretty destructive and spray pee and hump things generally. If you find these hormonal behaviors are disrupting your ability to get along with your rabbit, I would recommend getting him neutered.

“Exotic” veterinarians are the label for veterinarians who are specialized in non-dog/cat pets. That may be a better search term if you’re searching online in your area. You can also contact any rabbit rescues in your area and ask where they get their rabbits fixed.

Sometimes they just hang. Lol.

My last boy rarely had them tucked away.