Theory
I think because many people are buying now BTC due to "free money" the schedule to be at November ( BTC GOLD ) I believe that its price should go down because many people also transfer there funds from altcoin to bitcoin
And it good time to buy altcoin ( maybe wait even a bit longer )
What do you think?
I also think that people are buying bitcoin just for free bitcoin gold fork. And that's why the price of Altcoin is going down and bitcoin price is increasing, now it is struggling in $5600 range and it can go up as well as down.
And the best time for buying altcoins would be just a couple of days before the fork. As at that time there will be so much hype about bitgold and no one would be paying attention to altcoins so it will be quiet easy to get cheap altcoins at that time.