Sloaney1983

Could anyone please advise of the nuances of running a rollover for Gold futures. I have note traded for over 10 years however took out a Gold position 3 weeks ago on an August contract. My understanding is that this expires on the 28th of July (4 days). I have issued rollover instructions in setting and had e-mail conformation. Despite this I am unsure how this manifests itself. Does the rollover move to the December contract or just another month (Sept)? Are the profits realised or do they just continue to run? Do you effectively 'pay' the spread to IG again? Is this a better / more efficient way of running a position for longer if you are still bullish on the outcome or should you close and open a new Dec contract? Many Thanks for your time. Ed