Moving on to adult food!

[Charlibob]

At what age do you move onto adult dry food??

Jiminy is nearly 1 year old now and most dry foods say to move on to adult at 12 months but I've read a few bits online saying that they keep coons on kitten until 18months old due to them taking so long to mature.

So I'm pretty unsure as to when to change him over, hes right lazy lump (he has mad half hours running up and down the stairs but snoozes most of the time!) so I really don't want him getting fat on kitten food, when I do change over it'll be to RC MC as I like the sound of the larger kibble, if he drops a bit of the kitten food on the floor he can't pick it back up as its too small for his big mouth!