The nearest expiration date for PJM APS Zone Off-Peak Calendar-Month Day-Ahead LMP Futures (Jan 2017) is Jan 31, 2017.
The best time to sell a futures contract is when you've already made money on the investment, but still have plenty of time left before the expiration date. Thus, a good option would be to sell PJM APS Zone Off-Peak Calendar-Month Day-Ahead LMP Futures (Jan 2017) before Jan 31, 2017.