I got a call tonight at around 8:30 from someone who saw a cat that looked like Sonny (based on my door hanger) while they were driving by the intersection of Tartan Trail and Black Mountain Road. They said he was with another cat.
We drove over there within a few minutes with a can of mackerel and put some near a curb, then sat in our parked car and watched. Lo and behold, before very long, we saw cat eyes reflecting near the mackerel. We shined a flashlight on the cat and it ran away, but at a glance we both thought it could have been Sonny. We went back to the car for a while, then the cat came back. We approached the cat, but it ran away and then after that it didn’t come back. I came back half an hour later, and the mackerel had not been touched.
I will follow up at that location tomorrow with door hangers and will try to talk to residents. I didn’t get as far as Black Mountain with my door hangers over the weeked. The last street I covered in that direction was Marlborough.
Update Dec 11: I went back to the location again last night at around 10pm, and as I was parking, the same light-colored cat ran across the road right in front of me! Again, it was very fast, but it could have been Sonny. We don’t want to get our hopes up too much, but we will be pursuing this lead to try to determine whether it is Sonny or just a similar-looking cat.