The 10.1.5 PTR has been updated renaming it to 10.2.0 PTR on the Battle.net Launcher. While that PTR has yet to be updated with any actual 10.2 data, we might expect an impending PTR update or a reveal of what's coming next for WoW now that Patch 10.1.7 Fury Incarnate hits live servers today.
Below is the most recent roadmap of what content we might expect in Patch 10.2.