Your alcohol production and proportionate decrease in sugar content should be done during primary. Then you can age if you like. Since no more alcohol is being produced, it doesn't get any drier while aging. Most cider, especially those spiked with sugar, should be aged for several months before they reach their best flavor.
If you want something sweet, I would recommend allowing your fermentation to complete. Then sweeten to taste, bottle, and immediately pasteurize the bottles. That will kill the yeast in the bottle and allow you to preserve the sugar in the brew.
That also gives you the option of backsweetening with something like apple juice concentrate, in case your apple flavor fermented out.
And, as always, have nice day.