We're actively working on it everyday! As for dates, we can't give them. We update when we feel the update has enough in it to be worth the update AND that it all works as we intended.
As for the train, just to make sure we set expectations, this itch.io version is where the content stops. System updates, bug fixes etc will continue, but no additional content will be added (unless its things we add in the beginning levels, like our plans to expand the Horny Water for example)
All new content is available on Patreon (traing + 3 of the city levels so far).