Seems as though we have found out some more info on our Andy's background.
Mason walked Andy down to the mailbox yesterday. At the very last house, on the street around the corner, a man told Mason he recognized Andy. He went on to tell Mason that Andy, formerly known as "Champ," lived next door to him in the rental house. At some point, Andy got out and this man had him for about a week. He said Andy dug out of his yard.
Here is the thing.... that rental house has been vacant for a while now. It is not clear if the people left him when they moved out. That seems to explain why the man (neighbor to the rental house) had him for a week. That also would explain why there were no "lost dog" signs. Regardless, we don't have to worry about someone showing up to claim him anymore. They are apparently long gone.
Andy goes in for back -to- back treatments on Wednesday and Thursday. Poor guy will be out of it for a few days. Hopefully, this last cycle of meds. will take care of the last of the heart worms and Andy will get a clean bill of health.