HUGE thanks to everyone who sponsored me on this very challenging day! We did it in 14 hours and 50 minutes, starting and finishing in Stanley. Best-earned pint of Guinness ever at the end.
Unfortunately the app didn't seem to be able to cope with a different start-point than Central. After it kept pinging alarms - and then told us we'd "used up our navigation guidance" and had to buy a subscriber edition! - we scrapped it. Indeed technology was not a winner of the day - the app didn't work, Google Maps led us significantly astray a couple of times; my Apple watch (fully charged) died after three hours and Mike's iPhone after two. But we did it, despite almost a full day of rain and almost everything hurting by the end! Thank you again to all who supported. Not sure yet about next year... at least not in one go again!