HUGS. This sleep thing just never seems to get easier when you're in the midst of it. It will one day get better, I promise.
IMHO, if he's still having a lot of issues with NWing, he's got to be a bit OT, particularly if he's losing out on a lot of night sleep. In this case, I wouldn't do set naps right now. I would go by A times, but keep them on the shorter side to prevent a day of 30 min naps. If you know 3hrs or thereabouts works for him in the mornings, I would stick with that so that you are at least getting one good nap a day, instead of stretching it to 9:30am and taking a chance that he gets even more OT.
That's just what I would do, but someone else may have better advice.