Wirelessly posted (BlackBerry: BlackBerry8530/5.0.0.1030 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)

While it's impossible to predict what will be available when you are finally able to book, it might be worthwhile to see what is currently available for travel during the periods when you might travel. (Of course, you might have to wait a few weeks before you can see October, 2013, availability.)

It's true that UA offers more service out of DEN than AA does. But each of the cities that AA serves from DEN has nonstop service to Spain on either AA or IB. You can check AA award availability at aa.com; to check IB award availability, you will need to call AA.

AA's partner BA offers nonstop service between DEN and LHR, but long-haul award flights on BA come with hefty fuel surcharges, so it's best to ignore BA award flights that show up on your aa.com award search.

Good luck!