People who purchased Minecraft Dungeons along with the Hero Edition will be seeing the first of two DLCs coming in July with Jungle Awakens.
According to Mojang, Jungle Awakens will be a three-mission adventure in which players will have “new weapons, armor, and artifacts at your disposal.” Players will have to face new enemies like Poison Quill Vine, Jungle Zombie, Leapleaf and others.
As for Creeping Winter, this second DLC will be coming later this year.
Owners of Minecraft Dungeons should expect the addition of cross-platform play functionality and “cool new free content.”
[Source]: Minecraft.net: Minecraft Dungeons: On the Horizon.