The Walt Disney Travel Company in the UK just released their room only offer for 2016, not sure if or when this will result in lower prices on Expedia but worth checking back every few days.
The 2016 offer looks very similar to 2015's so here's hoping it eventually results in Expedia-UK offering similar discounts to what they offer in 2015.
For reference here's the 2016 Walt Disney Travel Company Free nights offer for European residents.
http://www.disneyholidays.co.uk/walt-disney-world/deals/free-nights-offer/021/
Stay in a Value or Moderate Resort for between 7 and 13 nights and receive 1 of those nights free or stay for between 14 and 20 nights and receive 2 of those nights free. Stays of 21 nights will receive 3 of those nights free.
Stay in a Deluxe or Deluxe Villa Resort for between 7 and 13 nights and receive 2 of those nights free or stay for between 14 and 20 nights and receive 4 of those nights free. Stays of 21 nights will receive 6 of those nights free.
Offer is available for bookings made between 16 Dec 2015 and 31 Mar 2016 for selected arrivals between 01 Feb - 15 Mar, 03 Apr - 04 Jul, 22 Jul - 17 Dec 2016, inclusive for participating Value Resorts and 01 Feb to 15 Mar and 03 Apr to 17 Dec inclusive for participating Moderate, Deluxe and Deluxe Villa Resorts.
Stays are subject to room availability.
Eligibility for the Free Night promotion requires minimum length of stay of seven consecutive nights, and a maximum of 21 consecutive nights at the same participating Disney Resort Hotel.
Offer is only available for the booking party in its entirety. For the avoidance of doubt individuals from the booking party are not interchangeable.
The number and type of rooms allocated to this offer are limited. This offer can be combined with other available Disney offers.
Offer excludes: Disney's Port Orleans Resort – Riverside, Disney's Port Orleans Resort - French Quarter, Bay Lake Tower at Disney's Contemporary Resort, Disney’s Polynesian Villas & Bungalows and The Villas at Disney's Grand Floridian Resort & Spa
Participating Disney Value Resorts Disney’s Art of Animations Resort (excluding The Little Mermaid room types), Disney’s All-Star Music Resort, Disney’s All-Star Movies Resort, Disney’s All-Star Sports Resort, Disney’s Pop Century Resort. Participating Disney Moderate Resorts Disney’s Caribbean Beach Resort and Disney’s Coronado Springs Resort and The Cabins at Disney’s Wilderness Lodge.
Participating Disney Deluxe Resorts Disney’s Animal Kingdom Lodge, Disney’s Beach Club Resort, Disney’s Boardwalk Inn, Disney’s Contemporary Resort (excluding Bay Lake Tower at Disney's Contemporary Resort), Disney’s Polynesian Resort (excluding Disney’s Polynesian Villas & Bungalows), Disney’s Wilderness Lodge, Disney's Grand Floridian Resort & Spa (excluding The Villas at Disney's Grand Floridian Resort & Spa ) and Disney’s Yacht Club. Participating Disney Deluxe Villa Resorts Disney’s Animal Kingdom Villas, Disney’s Beach Club Villas, Disney’s Boardwalk Villas, Disney’s Old Key West Resort, Disney’s Saratoga Springs Resort & Spa and The Villas at Disney’s Wilderness Lodge.