Yes. The APD will almost always be approved. As long as it does not fall on a holiday (cant remember which ones count as holidays, but think major ones) and there is like 15% of the required reserve coverage for the days you want to drop (Cant remember the exact percentage of reserves required). And it's up to 4 days in a row. In other words, you cant APD one day here, one day there...etc.

PD is a different animal. You HAVE to have above the reserves required available for the day you want to drop. Heck, you could PD christmas as long as there are more reserves than are required. You could PD as much or as little as you want, whenever you want, one day here, one day there, as long as there are more reserves available than are required.
Your APD renews at the beginning of the month you were hired in. If hired on Nov 29th, your APD resets on Nov 1...so use it if you have to before then so you dont dip into the current years one.