Yes, we do have to key it again. I must say I find it quite boring to key them all over again, and when I get to a second or even third page with lots of the same people on I usually take a break from keying that set and leave it till the next day to continue.
I think it would have been better if there was 1 image per image set and the sequence was shuffled so that keyers were unlikely to download consecutive days' papers together.