I think that setting the bug status back to "New" is the most appropriate thing and that having two definitions of Confirmed, somebody else recreated this bug vs the reporter responded, would be quite confusing and make it harder for people to participate in bug triage.
Perhaps instead bugs could have an untouched(?) bit that would distinguish between brand new and needs reanalysis bugs.
I think that setting the bug status back to "New" is the most appropriate thing and that having two definitions of Confirmed, somebody else recreated this bug vs the reporter responded, would be quite confusing and make it harder for people to participate in bug triage.
Perhaps instead bugs could have an untouched(?) bit that would distinguish between brand new and needs reanalysis bugs.