It's going to be a long time or it's never to see bitcoin under $4,000 again. We did struggle on passing $3,000 - $4,000 before and you want to see it again back there? Nah, the price is good at $6,000+ now and it's very possible that we've got new floor.
The price surpassed 7k today, and as we know bitcoin can move down normally up to 20% down without anyone considering that a crash so if that happened the price of bitcoin ill only go down to 5600 far away from th price the OP wants to see, so I think it is safe to say we have leave behind the 4k price for good.