Read the wrong haftara. Now what?
Suppose someone started reading a haftara for a different week, or according to a different custom for the same week, or a piece of navi that's not a haftara at all. What should the community do?
I suspect the answer may depend on when the mistake was caught (after the closing benedictions were made after the haftara, before them but after a few verses were read of the mistaken haftara, immediately after the mistaken haftara was started) as well as on which haftara is being mistakenly skipped (specifically, whether it's one of the three of retribution, seven of consolation, and two of return that we read each summer, which I understand may be more mandatory than other haftaros). I'd appreciate answers that address as many of these cases as possible.