I totally and 100% agree and I'm not saying make him an indoor cat... definitely not. All I was suggesting is keeping him inside for 4 weeks if possible before letting him out (run or no run)
But regardless... wishing you best of luck tomorrow; I really hope operation "Nab George" goes super smoothly and he settles in his new home very soon. He's a lucky boy and I'm looking forward to a photo or two x