Since I'm 99.9% sure that we'll never see a Next gen. movie any time soon. Have there been any novels dealing with the possibility of Data remerging thru B4 (or by some other means)?
There is one story in Strange New Worlds 10
in which that happens, but in the novel continuity, there's essentially zero chance of that happening. B-4 is a far cruder model than Data, and can't process Data's entire memory and personality any more than a Commodore 64 could run Windows Vista. Even if he weren't a bear of very little brain, the download he received from Data consisted only of memories, not personality. He wouldn't turn into Data any more than Data turned into Lal when he downloaded her memories.
In the books, B-4 is in residence at the Daystrom Institute, being studied by Commander Maddox, who (in a complete turnaround from "The Measure of a Man") has been a stalwart champion of his right to be judged sentient and protected from disassembly. The last we heard, the Federation Council granted B-4 that right (as seen in Articles of the Federation
and alluded to in Greater Than the Sum
). But what B-4 does with his life, or if he's even capable of learning and growing at all, remains to be seen.
If I'm not mistaken, it seems that a few times it was alluded to in the Next Gen. series that Data would be around far into the future.
We also saw possible futures in which Troi had died, the Enterprise-D
survived and had three nacelles, Riker became the captain of the Enterprise-D
, etc. The future isn't fixed.