I would keep checking daily to see if other dates become available. I didn't realize that I was lucky and they were only good for my arrival date. I checked about 10 different dates and although Lion King and Family Suites how up I don't see Little Mermaid on any other date. I would guess either they will remove it from my arrival date or they'll add other dates in. A week ago I posted that I saw
free dining for the Family Suites and went to the dentist and came back and they were no longer showing up at all. Didn't see anybody post that they got it. Today I check (as I do a time or 2 every day in hopes of getting it) and noticed the "excludes Art of Animation" wording was gone. I check my dates and there was the Little Mermaid section as well as 2 other suites. I called right away and switched no problem. I'm guessing more will show up or they'll remove Little Mermaid altogether but at least I'm locked in now.