I think the percentages given from hard cider above are misleading. No offense intended. The procedures given are basically correct, but here goes, Apple Jack does not have heads or tails, that is only from distillation. When it comes to Apple Jack hangovers, in my experience, it is caused by too high fermentation temperatures and how stressed the yeast were causing fusel alcohols at the top of their fermentation temp range. My first batch of hard cider wasn't worth talking about, as it smelled like nail polish remover. Temps were way too high because I didn't treat it like beer and control the ferment. Back to the original idea: 1) there are no heads or tails, 2) removing the alcohol is easy to do. Depending on the temperature of your freezer, will for the most part control the amount of alcohol available. If the bottle/carton, etc., is frozen mostly solid, the first drippings will be very high proof and flavor concentrated, and as the color fades out of the ice, so does the alcohol concentration. Let me make this clear: just because the ice is now w/o color, that does not mean all the alcohol is gone. Let the ice completely thaw, and put it back in the freezer again. Percentage wise, the alcohol ice will be very weak, but there is some left in there. How much time do you want to take up? A couple of things: you can use any sugar source to add to the cider, white, brown, agave, etc., will strengthen the ABV, but the flavors made I really don't want, I want apple. I will use a 12oz can of FAJC into a 2 liter bottle, and top the bottle off with pure juice or cider, and hit an O.G. of 1.080 or so. You could add 3 cans of concentrate and top off with water to 64 oz total, or, of course add what ever you want. Using concentrate with juice is my favored method. Keep in mind two things: the higher the ABV, the longer it will take to ferment, and keep your temps as low as possible to avoid off flavors. I use London ESB 1968 yeast, as it is my house strain, and makes a nice cider. This yeast doesn't eat all the sugars, and clears quite well when made into bottled cider. As well, it makes really smooth AJ. I like my AJ a little on the sweet side to smooth it out even more. I hope this helps you out.
EDIT: It would seem since hard cider gets better with age, that AJ would also get better with age. Does anyone have experience with aging hard cider/Apple Jack?