High alt? Dude, you were in orbit!
Exploiting game created flaws (aka, d1.2+ buff turbolasers + 30k buffs outperform fighters + FR hit of buff formations) to hit targets as vital as the HQ is outrageous and lame. Its almost as bad as flying off the map.
Stick to 20-25k and bring escorts, the result will be the same and you will save 20 minutes of your gaming. Heck, 2 lancasters with 2 escorts at 25k have a good chance of killing the HQ. 10 b17's at 35k attract a hell of a lot of attention. And they die.