It depends on when someone is willing to buy your coins at that price. Basically, your order is in the market providing liquidity for buyers. They need to buy all the sell orders in front of yours before they start buying yours. First come first serve basis. There is no way of telling when the order will get filled, the price could crash and it could be years before it gets hit. Or it could skyrocket and hit your order instantly, it always depends on the volatility of Bitcoin.