Yes, you have to be 18 or older to play in the AHL.
One more year of Junior isn't going to stunt Horvat's development. It will be nice to see him get his 9 games in the NHL and hopefully he will be able to stick around for the full season. But if he doesn't get his chance to play in the NHL and is sent down to London then it's no big deal or as Jared Mccann would say, "it is what it is". With that said if Horvat is sent down to London I would like to see him put in an offensive role. No more playing as the shutdown center, put him with Domi, and a guy like Mitchell Marner who is ready to have a break out season. He is solid when it comes to defensive play, but I feel like there is more for him to show on the offensive side of the game and he's not going to have a chance to prove that to us and himself playing with 2nd tier players.