Solved! Solved! Go to Solution.
You say "imported abc.1 as abc.2", does that mean you didn't hit the "Fork" button to create this repo? If so, it's not actually a fork and you cannot file PR's from abc.2 into abc.1 I'm afraid.
Ya I don't see how this will be possible with the web interface. While its true you can't directly submit a PR, with a bit of extra effort I think it should actually be possible. Since the guts of a PR is really little more than a patch file (which is basically a git diff) you could then fork the upstream repo, apply your patch to the fork, and then submit your PR upstream. The integration effort depends on how much deviation there is from the private fork (were changes integrated back in for example) Depending on the project the maintainers may be willing to take a patch file directly via an email or on an issue and apply it for you.