Dagor Dagorath/Turin returning?

[elbenprincess]

I´m confused with all the versions of the last battle. In one it is said that Turin will return either from Mandos or from beyond the circles f the world. In another version Turin will return in the War of Wrath, kills a dragon and then left for ever the circles of the world and will not appear in the Dagor Dagorath, insead of him Eonwe will end Morgoth.

And what is all that with Turin to be counted among the gods? I´m not sure, in an old tale? Turin and Ninior are counted as Valar even before the last battle, while in the version Turin takes part in the battle he will become a Valar (nothing is said of Ninior).

I couldn´t really find what Tolkiens final view on that matter was.

Is it right that the version where he takes part in the battle and becomes a Valar is an old one and the other version where he doesn´t take part in the last battle and therefore doesn´t become a Valar is a later version?

Which version do you prefer? The version where he becomes a god or the version where he doesn´t take part in the last battle?