We have other cats in our family that Max has known for a long time. Two in particular, Count Chocula (a tuxedo) and Daphne (Siamese). Of all our cats, they seem the most likely to stay in touch with him, if he were somewhere in the neighborhood.
I thought it might be possible that one of our other cats might know where Max is, if they were visiting him. So I got a couple pet trackers, a Jiobit and a Whistle, signed up for their data services, and put them on the cats. Then I collected the location telemetry for each cat's excursions.
The light maps are from the Jiobit and the dark ones are from the Whistle.
These locations show where the cats have collectively visited over the course of a few weeks. It's just a start but I intend on collecting more data and seeing what else it may show.