I want to preface what I'm about to say with all the cards on the table. I personally prefer the current incarnation of Superman compared to his New 52 counterpart. That's not to say one is superior to the other,and that's not to say I didn't like many aspects of the New 52, because I certainly did. However,i thought that the degree they rebooted the character to get to those changes took away more than was gained and while the core characterization of Superman WAS much improved from what the prior version devolved to in it's last few years,much of everything else ,in my opinion,because I'm only speaking for myself,was a giant step down. What was gained from the reboot ( a characterization closer to the PreCrisis version of Superman or at the very least a more assertive Superman) could have been accomplished with better writing and hiring writers that got the character,and didn't require a quarter of a century's worth of continuity and world building and stories completely being tossed out and replaced with....well... really not a whole lot.
However,i did not and still do not approve of how DC has handled all this. Doing a cut and paste job is convoluted as all get out and only served to further muddy the waters. It would have been more simple to just retcon in the alterations via the " missing" time to steer Nuperman towards a more classic take on Superman or to even bring about the return of the Marriage and Jon's existence. Not everyone would have liked it and some would still would have belly ached over certain ships going away or complained about the idea of Superman being a father ,but at the least we wouldn't have to go through the convolutions of,say,Lois Lane having to be killed off and having another Lois Lane take over and everyone being okay with it,as we saw in the recent ACTION.
Now having said all of that...
We were told in the REBIRTH special that the New 52 is indeed the preFlashpoint universe,just altered via meddling from a third party whose motives are yet revealed. Meaning the Batman of the New 52 is the same Batman as before,but with altered memories. Same with Flash,Wonder Woman,Green Lantern,etc.
Now,assuming Superdad is indeed his preFlashpoint self ,and he missed having his memories altered because of events outside of his control,ans assuming Nuperman was some sort of anomaly and replacement.... can the argument be made that technically speaking,isnt Superdad and by extension Lois just reclaiming their actual lives and Nuperman and his Lois inadvertently were actually the interlopers that " stole" Superdad and Lois' place in the world?
The very fact we are forced to consider this is telling but....well...we are already here. Truth be known, it's not as cut and dry as Perhaps it looks on the surface.a case could be made for either being the interloper who stole the other Superman's place.
So the question is..who is the real interloper? Nuperman or Superdad?