Glad he's back. There's nothing more worrying than your cats not coming in when you expect them to.
Mine have been going awol a lot recently, I'm sure it's the good weather, but I worry when they don't come when they're called (as they usually do) but as you say, just as you're about to send out the search party they jump over the garden fence as if nothing has happened! I'm starting to worry less now, as they DO finally come back, just in their own time. As long as mine are in by dark I'm not too bothered anymore. It's not helping that I'm on leave at the moment, so feeding them in the morning later than usual, so I guess they're not too hungry when I want them in!