Cheers all, it's helpful to get a few thoughts from outside my own addled brain
This will be the third one (5 year screenings due to family history) and if it's anything like last time the purge will be more exhausting than the procedure. I've had a bit of leg cramping the last week or two which I've put down to messing up electrolyte balance in the warmer weather so that's probably more of an issue with the time available to put it right around the low residue diet and Moviprep.
Last night's 18k over Stanage and Burbage in the dark was a bit of a car crash (3 hours!) so I'll see how it goes these next few days, the confidence issues might just be inside my head right now.
Post edited at 09:12