I hope they clean them up. If I want to see a yellowing comic I can look in my box of progs. I want to see them in their pristine glory.
Question is how well can those older covers be cleaned up if they are scanned from printed comics?
And how much 'pushing' of the colours would they need in order to look as if they were on pure white paper – which is not how they originally appeared.
Some of those older Marvel reprints on super white paper look terrible to me. Originally coloured brightly to compensate for the absorption of ink and dulling effect of newsprint stock – they look garish on pure white paper. But at least (it seems) they are reprinted using original artwork – bromides, films, possibly original colour separations.
Now I would guess Rebellion doesn't hold all that in its archives. I don't care for images that have to be retouched so heavily that they become a poor version of the original covers. I want to see them how they were intended.
But 2000AD has an excellent design team. I'm sure they will find the best solution for the older covers whether the book is design in house or externally.