...whiz: I see what you are talking about: Why is there a mag heading displayed even though the alignment process is not complete.
Check (and I will too) how soon after you put the system in align mode the mag heading will appear. If it's there immediately, maybe it is a remebered heading from shutdown?? Depending on where your latitude is, consider that even though your INS has the same alignment period allocated for every alignment, it provides PPOS and heading much sooner at lower latitudes than higher. The INS on my plane always counts down 10 minutes before it goes into nav, but it might take only 2 or 3 to get all the calculations done when I'm on the ramp somewhere in Central America, close to the Equator.