Does he have a day sleep?

If this works for you at the moment then stay with it. Sleep patterns do change and as he gets older and more active he will get tired and be wanting to go to bed earlier.

DD1 now has a night light in the boys room so they 'read or play' by that and she has found they don't get out as much as they used to.

Some kids need more sleep than others and as long as he is not sleeping in then stick with your method.