Board Thread:Manga/@comment-5774380-20160609000528/@comment-5774380-20160628011612

It's not an epilogue for the whole story, but only for the events of the chapter. As I previously mentioned, we already got an epilogue for chapter 50. In that chapter, Reiner, Bertolt and Ymir were attacked by the Titans commanded by the Coordinate, and their fate remained uncertain after the Survey Corps returned to the Walls. When the chapter was compiled into Vol. 12, it added four extra pages at the end, revealing that they managed to escape from the Titans and reach Shiganshina. That was the epilogue.

I must say that I'm not sure if Isayama actually said that Vol. 20 will contain a similar epilogue. Fukushuu's translation says "epilogue", but it could also be an error of the translation and Isayama probably said "read until the last chapter"; i.e., chapter 82. As I don't understand Japanese I can't confirm first-hand.