John,
October is getting a bit late for backpacking for me. I'm only planning one more trip up Whitney after this Saturday (if I can get a permit), and it'll be via the Mountaineer's Route. The only time I'd backpack for Whitney is to go up Russell as well (which I plan on doing this year), but it'd have to be before October when the days are long, the temperatures are higher, and the ground free of snow.
Who knows though, if I do go again in October, I could join you for the first or second leg of your trip. If like Steve said, you're going in October because you're worried about getting a permit, I got one last year on the Memorial Day weekend.
