jaelis
Oh this is where the title goes?
Not to mention, if you do not place Hex on a target, then it ends. You can use a bonus action to move it, but you still have to satisfy the conditions of the spell (a target you can see within 90 feet) -- you can't just hold it "in reserve" focused on nobody.
The spell doesn't say you have to place the new hex immediately. See also
http://www.sageadvice.eu/2015/10/02/hex-concentration/