Or he might be old even now.The canon leader of the Iron Wolves circa the 2520s is one of the greatest of Tzeench's Chaos Lords, and one of Archaeon's lieutenants. But he might still be a kid, so it will likely be a roll, so I agree that we should be careful here.
Chaos Champion after all.
I would be careful assuming that age is an issue for one of them. It certainly doesnt seem to be an issue for their 40k cousins.