For the price go down again to 400 some serious things need to be happening. I don't see this coming, since we got a positive market.
Perhaps after the halving?
The big whales can push down the price briefly down to $400. But it will not last long, the value is there.
Big whales can do anything they want with the price. But they want to profit from it, so why dump a lot of coins to lower the price if they can sell them slower and profit more?
You can already see now that the value of Bitcoin will rise for a long time now and that is because it was stable for a long time and the halving is also coming towards to us.
But nobody will ever know what is going to happen in the future and that is the problem of the currency.