FWIW, I'll throw this out there: granted Kings and corns are different species, I've always fed them the same way.
That being said, Django is about 52" and 772 grams and gets a LG mouse (18-32 grams, but most fall in the 24-27 range from Perfect Prey) every 7-10 days. He does occasionally get a refusal from one of the others as a treat, but his regular diet is one Lg mouse/7-10 days.
On that diet, he's still growing too. I got him in Oct 2016 and he was about 49" and 645 grams.
He pees and poops after every meal and is in great bodily shape. He's solid but not plump, no loose skin. He's firm and lean muscle throughout.
So, as long as he's still looking healthy and growing I see no reason to increase prey size and no reason to cut back to a 10-14 days schedule. Once I notice he's plateaued off with growth I'll probably cut back to 10-14 And see what happens.
Just throwing this out there as food for thought.