My dd 10 has similar numbers, and she has taken classes through CTY, so I will chime in. First, I like ultramarina's suggestion about non-academic challenge. An instrument, perhaps? We are very relaxed homeschoolers, just so you know where this is coming from, but I am a huge believer in free time and imaginary play. Your DC is pretty young. Yes, I think gifted kids need to be challenged, and you could probably wait a year before pushing that as long as your DC is happy. I know some PG kids really crave academics early. That was not the case for my DYS dd. She was happy to hang out and read and play pretend when she was that age. So unless your kid is asking for it or super excited to try it, I would suggest holding off a bit.
However, if your DC is on fire to try something through CTY, then maybe take a look at the self-paced courses. Because you can take them at your own pace, they don't have to be terribly demanding in terms of time. They will just take you longer to complete. My dd is taking a cryptography class now that is definitely challenging her. She does enjoy it quite a bit. She is doing lots of other things, so the class is taking awhile to complete though!
