Vantage Roadster soft top head lining sagging

[two sheds]

when l raise or lower the soft top on my 08 Vantage Roadster the last fold on the head lining before the rear window drags on the tonneau latching clips and it is now wearing holes in the lining.
When the hood is up it is just possible to see with close inspection that the lining is sagging at that point, my question is has anyone else had this problem and is it possible to gain access at this point to do remedial work without stripping the whole hood.

[PatCub]

Not 100% sure but there are a number of cords that run from side to side, check these for tightness or if one has snapped.