Oh if it hits 4, then you sell, no question. It can't keep going up and up forever. In fact, if it hits 3, you sell because it is more likely to go down than up. If it hits 3, sell and wait till it gets back down to 2.50 or so, like CNBX did last 3 days.
However, that's a long way from happening. Right now, it will stay in the 1.10-1.60 range for a while.
Seriously though, you are looking at a major loss as it stands. If you are that confident that the price will go back up, then you should buy a few more shares at this price. That way when it goes back up, instead of blowing even, you will have a profit. If you do buy, buy under 1.30 for sure, and preferably under 1.20.