We have approximately half of Act 3 written and many of the art assets already done! The game needs serious optimization and some code updates which will definitely take some time. Ideally it'll take less than a year to get to the Act 3 public release since Act 3 is more of a content push than the prior two acts.
Act 2 took extra long because we had more "requirements discovery" as we fleshed out Act 1 designs and gameplay mechanics. We added all kinds of new stuff like critter dates, illustrated stories and critter gifts to give players a richer experience in the Forest. There are several new minigames to design, but we mostly have the tools in place now to tell the story we want to tell. :}