Rest of SWTOR Ziost story will be accessible starting May 4th and does not require a patch. This may open up the new daily area and world bosses.
Planetary Status Monitor | Still no progression in Ziost story available ? | 04.28.2015, 06:30 PM
Without spoiling anything, there have been some questions about the end of Ziost currently and whether this is intended or not. It is 100% intended, it is not a bug, and there is definitely more coming… And it is coming soon. The finale event for this story will happen Monday, May 4th and it will not require a patch.
Evacuate Ziost while you have the chance!