I’m only 5 months post-op from my urethral surgery, but I have a lot of experience with nerves healing from other surgeries.
It’s probably just nerves coming back. Sometimes the brain will shut off “noisy” nerves after they’ve been injured, essentially ignoring them. Eventually it will sometimes listen again, once they’ve healed somewhat. The other possibility, and the most likely one, is that one of the nerves that was cut during surgery has reconnected to another nerve, and is back online again. They grow incredibly slow, and can take up to 2 years to finally find each other.
They’ll settle down eventually, it just takes time.