Totally valid, and actually prompted to add that photo below. But I think the exact same applies regardless.
I wasn't being flippant with my 'why not' btw. I will expand on that.
It wouldn't have originally been built in one piece, that wouldn't be possible. It would have been built in sections/segments. As such, then surely it can be repaired in sections, replaced in sections, or dismantled in sections. And if that's the case then those sections/segments can also be replaced with other sections of a different design or configuration, IF, they perform the same role.
I am assuming by the cable net, you guys mean the red and blue highlighted in image 1 below. Deliberately used two colours to show the north and stand segments of that, and where the break is, and it is a pretty clean one.
Then the same image with the proposals crudely overlaid. To me, it looks like the existing north stand portion of that is being replaced by the new roof higher up, and the rest of the east and west stopped at the vertical junction to it. It is how they restrain those ends that it could hinge on. But I don't see the cable net continuing, I see it interrupted and replaced for that portion of the stand. It doesn't seem to appear below the roof either. There is a clean break betwen GL N4 to N17, imo. Could be wrong.
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And an old image ofnthe cable net pre stand as mentioned by you and Phil
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