if btc retraces 30 to 40 percent when it hits 13k to 15k what will happen to alts will they fall as well or will they go up or how would it play out?
Alts seem to get funded well only when Bitcoin is "loaded" and the money flow into starts to slow down.
When Bitcoin jumps alts fall behind; when Bitcoin falls, alts also fall, sometimes even more than Bitcoin.
So for your use case (bitcoin falling) I'd expect the altcoins fall. However, if Bitcoin will not fall and will only slow down, then the equation changes completely...