Letting cat outside after move

[CantChoose]

Moved with CantCat 5 weeks ago. He only started asking to go outside in the last week (very unlike him to not ask so we just left him to it!) so we let him out today before breakfast for 10-15 minutes.
Should we let him out again today and just leave him to it? Or wait until tomorrow, build it up gradually?? Reading mixed things online.
He's predictably sitting by the back door neowing now, of course!

When I moved with my cats, the first week they were kept isolated from my friend's cats, but they were all able to see each other. Then we left them to mix in the kitchen while we nipped out and when we came back, all 4 moggies were in the garden. I didn't know mine (who were rescues) could use a cat flap. After that, we just let them out. I did have a worrying day a couple of days later when Candlecat2 was out all day, but he came trundling home in the early evening. I would say let him out now.