Puppy is now 10 months old and has lived with me for 6 months. Most of his nerves have gone (he does still cower a bit around new men, but it's not all the time and it only lasts for a moment before curiosity wins out and he sniffs.) and he seems to be happy and healthy. He loves other dogs more than anything.
I bring him to work with me, so he's used to being around people and dogs, he's calm in the office and gets plenty of walks during the day. I feel like I'm doing pretty well. Except today, out of the blue, he attemped to cock his leg indoors, against a person's leg. He had been sniffing her first, so I'm not sure if he could smell her own dogs and was reacting to that.
I was aiming to put his castration off 'til after his birthday in March, but am now thinking it might be time to consider moving it forward. I've only once seen him mount another dog - although I'm still not sure whether he was just trying to wrestle - he's a small dog, probably about 15kg, and was playing with a full grown labrador (castrated), so it's possible he was jumping up to try to pin the other dog.
So yeah... I was just wondering if there's any big difference between getting it done at 12 months or at 10. I'm about 90% sure I'm ok with doing it now. He's a small breed, and size-wise seems to have stopped growing, so I'm happy that castration won't have any adverse affect on his growth/bones/etc.