I can't find anything online but I'm guessing that the work we saw today is part of the BMC Mend Our Mountains campaign.  Bags were being flown to various parts of the Kinder Scout plateau, but they contained dried heather, not stone, so perhaps it's a way of reseeding?

What a walk today with Derbyshire Dales Ramblers!!  From Barber Booth up to Brown Knoll, Edale Rocks, Kinder Downfall, Kinder Gates along the plateau and down somewhere I've never been down before... very steep!

12.97 miles
2676 ft ascent