The TD organizers keep reiterating that the SPOT trackers can accidentally turn off. Several racers appear to be still at the start. They are fairly accurate when turned on, but lack of movement should be interpenetrated as a possible SPOT failure.
When reading the webpage showing Kent's progress on the SPOT, there are only the last 50 points are displayed (numbered backwards for some bizarre reason). Fifty points can be considerably less that a full day (we're seeing on average about 70 points a day). You can check the previous pages for previous points. Unfortunately there appears to be a maximum capacity for the display -- i can't tell if it's 7 days, 350 points or 10 pages, but points from about a week ago are disappearing.
I have not been able to figure out how to download the tracking points from the SPOT page although it has been suggested that it is possible. If anyone figures that out, please let me know - it would be great to store them.