If you want to keep with that routine then yes I would suggest waking at 6am otherwise it may become hard to get him down for that 9am nap or for him to sleep a decent length, which you need.
If you don't mind the earlier WU time you could even bring BT a little earlier, this could really help with night sleep, his last A is very long, I'd be concerned about it causing some problem - but if it works it works!
The other option, perhaps not now but later, is to let him WU later, move the first nap later and the second nap to after school pick up, shifting BT later (and round again to morning WU being later).