I don't think AP rates have historically been offered in October. Current AP rates run till September 30, and are $231-$259 per night plus tax for Grand Floridian Garden View.
As far as I know, October is one of those "no discounts" times. You can, however, get a Disney Club or AAA discount (10%) at the GF in October. There may be an occasional discount code as well (none have been released yet). Fall Fantasy Packages are out until October 2nd arrivals as well. It will give you a small discount, but the Unlimited Park Hopper is included.