As noted, Samoa Joe is scheduled to move up to the main roster sometime after WrestleMania 32. There has been some talk as of late of having him make his main roster debut on the day after Mania on Raw. His debut could be delayed if he beats Finn Balor for the NXT Championship at Takeover: Dallas.
NXT Champion Finn Balor is scheduled to make his main roster debut at the end of this year. Dave Meltzer mentioned on the latest edition of Wrestling Observer Radio that WWE currently has short-term plans for him in NXT as the face of the brand.