I just watched Wainwrights walks on BBC 4 andI was very surprised that it took 10 hours for Julia Bradbury the walk up Scafell Pike G/LD-001. When me and my Dad M1EYP have walked up Scafell pike, it has only ever taken 4 hours to get to the summit.
When she was on the summit it looked to be 6pm in the evening due to where the sun is. Also her rucksack was very small. She still had to decend back to Seathwaite and she should have carried all camping equipment.
In conclusion, I don’t think she did the full walk there and back. I think she was on a helicopter for most of the walk there and back.