Technically nothing is impossible.
They could also give us a final 20 animal + expansion with aquatics and birds and whatever.
Is that likly to? Not at all id give it a 0,00000001% chance.
The same goes for just more animal packs then we are used to. When we got the 5 year anniversary celebration pack and didnt even get the usual exhibit animal because we got like 50 new pieces, in what world do we get 12 animals in any pack when it isnt a simple case of swapping textures like the butterflies? The only context i see us getting more then 8 animals again is if we get more butterflies, but thats never what people who bring more animals up talk about.
Also guys, may i ask why 12?
4,5,7 and 8 are the usual numbers, 10, 14 and 16 would be us getting twice as much but why 12? Its such a random and arbitary number and again if its because of grasslands its because 5 of the animals were literally just texture differences from each other with no unique sounds, animations, model differences, etc, just another pair of wing textures slapped on the same basic butterfly model. Dont get me wrong this works great for the butterflies, but how can the same community that had a gripe for years with the malayan tapir being just another texture over the bairds tapir also go like yeah lets just get 5 different textures on the same model for birds, frogs, tamarins or whatever else gets suggested.