I have a number of things (variables) that leave me in a state where I am not sure when I should sell. In one scenario, I definitely would not sell until after the New Year.
Because of that I looked at some scenarios like the one you mentioned. However, taking yours for instance. If the price of the stock drops drastically before Jan, your insurance still cost you 8 bucks per share. The 3 dollars you paid for the options plus the difference between today's price ($20) and the strike price ($15).
I calculate that 8 bucks is too much to pay to protect a stock at $20 in which most (not all) of the risk has disappeared.
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