According to Christopher
Tolkien, the Second Prophecy of
Mandos was definitively abandoned by JRR Tolkien,
and Christopher Tolkien provides the evidence for this in
The History of Middle-Earth series, some of which I have quoted more than once in these glittering
halls.
Christopher Tolkien never stated that the
Dagor Dagorath was abandoned, but he (once again) provides the Tolkien written evidence for the description at the end of
Quenta Silmarillion (which had before been the Second Prophecy of Mandos) becoming a
mannish myth of
Númenórean origin.
This is a notable re-characterization from JRRT, which goes hand in hand with Christopher Tolkien's evidence that the Second Prophecy was abandoned.
Moreover, we can also add the prophecy of Andreth here, which arguably raises questions, at least, as to
Túrin's role in any "end times scenario" -- a point that we've discussed before if I recall correctly.
🐾