Farm Story Expansion Disappeared

I'm not sure if I missed an update to the original Farm Story game but I've been expanding my farm and I'm currently at 24x24 and I went to expand again a few days ago and now the expansion options are gone. The biggest expansion option available was a 40x40. Did the expansion options change to a smaller size and I'm now maxed out or am I missing something? Some clarification and explainations would be greatly appreciated!

The current maximum expansion is 24 x 24.

21 x 21 level 40: 600,000 coins 40 neighbors
22 x 22 level 50: 700,000 coins 45 neighbors
23 x 23 level 60: 800,000 coins 50 neighbors
24 x 24 level 75: 900,000 coins 55 neighbors

When did the options change? And why?

The list that renetory2 posted has been the expansion list for years.