I'm in a similar boat as you. Will be looking somewhere around mid July for 2 BR. There's a good thread about studio availability and trends that's always near the top of the forum. I know they only look/predict for Studios but I'd have to assume the 1 and 2 BR categories are at least as good of a chance. According to the studio availability at 7 months july through august looks pretty good the higher up the room type you go.
I'm sorry that I don't know the answer. But I'm interested in knowing... I was thinking that we'd go to DL/Aulani next April/May and I wasn't planning on starting my planning until after our early Dec. WDW trip... if that makes you feel a little better. Perhaps I should rethink that.
We’ve gone in July/August 3 separate times and each time had no problem getting a studio ocean view for anywhere between 14 and 21 nights. Ocean view is generally the easiest availability, so you should be ok. Good luck and enjoy, it truly is amazing! We can’t wait to go back