Maybe too many people are eligible, but we have never had a problem booking a room at any Disney resort with a military discount. (LOL, except during Thanksgiving - THAT was impossible.) Keep in mind that this is also an option.
We just booked Wilderness Lodge a few weeks ago, and I don't even know if my husband will be home by then. But by no means are we ever going to be able to book 9-12 months out. God only knows where we will be 9 months from now! We changed resorts and dates DOZENS of times when it came to our original thrown together honeymoon in February, after which he was immediately sent "over there", but we didn't have any issues booking a room at military rate at any of the resorts.
Then again, we seem to only go during value season, so that may have something to do with it, but if there's not any rooms at Shades of Green, you CAN get a room at a discounted rate throughout the WDW Resort. (You can book through SoG or CRO, if you're booking through CRO, just mention that you will need a military rate.) He always likes to be as far away from anything "military" when we're on vacation anyway, that he would prefer to NOT stay at SoG.
What is worse than the issue with MWR leasing SOG is the Armed Forces Salute tickets that a lot of the armed forces who were directly involved with this war will NOT be able to take advantage of. I booked for the last week that these tickets were available, and we're PRETTY SURE he may be home by then. If he's not, then this is the second war in a row where we missed out on that. THAT is sad.
LOL, point is - if there's no room at SoG, try their overflow rates at the Disney resorts.