Okay I feel that I need to explain the terrible gibberish English. I shouldn't have to. But Khara failed, and I don't want to see people speculate and make jokes on bad English.
The first part of the poster says "A continuation, and then the conclusion." It's pretty obvious that it refers to how the next movie is assumed to be the last one. The second part of the poster is more vague and harder to translate elegantly without know the "secret" intended context, but I'll say it'll probably fit as "A mistake, and so we must oppose." This is Anno so I can't say I know exactly what it is intended to refer to, but the surface reading is very clearly meant to suggest that they are aware fans didn't like 3.0 and it could suggest a sort of redo or retcon.