@DiscoSteve , I've seen you ask this a few times here and on SSC, re the old large drainage chute.
The proposals are for this to be replaced with similar chutes either side of the new stand projection. There are also 2 similar ones within the square for the erfe roof. Circled in red below in various locations.
As for the current temporary set-up, can't see anything in place in fairness, there is either a temporary solution we can't see in the drone videos, or possibly they are just accepting they live with it during the works.
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