And there may have been a time differential in the book as in Narnia where no matter how long the characters spent in the other world they come back at the same point that they left their world. And there may be a time differential between worlds. All of that is possible, but the Hatter was in Storybrooke and has been trapped their for the last 28 years, so i think that the events of Alice in Wonderland happened before Emma was born.
Also it didn’t seem like the Queen or Jefferson were worried about how much time was going to pass in the fairytale land while they were in Wonderland so i think that it is unlikely that time is working differently between worlds meaning that if you pop into Wonderland for a day, three centuries could go by in fairytale land. No one would risk that. And it seemed like this was not Jefferson and Regina’s first trip into another world.
The first thing may be possible, that no matter how long they spend in another world they return to their world at the exact moment they left. I don’t want that to be the cause because i don’t want Emma to be a baby at the end of this series. I like that idea as long as it does not apply to the end game of the show.
Though that does beg the question of how does the real world know about the stories from other worlds and those stories are old known stories in our world.