The roof won’t make much difference. At the end of the day it needs to be there for North Stand level 1 and the OG level 2 by the time the first game starts in August.
The only time they can take down the original roof is during the close season because they need mobile cranes on the pitch to do it and these will cause some damage to the pitch so the work also needs to be concluded several weeks before the new season starts.
Expect all the initial roof beams to be in place before the end of April and perhaps even cabled up by then as well.
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