We have plans to deprecate an older web endpoint, AvatarAccoutrements.ashx, we are targeting this change to happen on July 9, 2018. We encourage you to make any necessary changes that you need to prepare for the switch over to the equivalent Lua API, GetCharacterAppearanceInfoAsync.
You can learn more about the newer API through our Developer Portal:
If you have any questions please feel free to reply to this thread.
Developer Relations Team