Board Thread:Show-Related Questions and Answers/@comment-25315804-20180521051258/@comment-24720945-20180521114644

After Rumple's death, Zelena, Snow and David returned to SB. Then, Gothel's curse was undone by Regina, and it took everyone in the wish realm to the future. At this point, Gothel's curse has been cast, and Regina merged all the realms.

I think this is what exactly happened. It explained why W!Henry is still young after the merging of realms, as well as the fact that they didn't change a bit of the past.

But I'm not sure about Kelly. Did she just disappeared from Chad suddenly when she was taken back to the future?