My thoughts are as follows: Site Tau and Site Phi and Site Omicron have been afflicted by potential clock inaccuracies, so some time 12/24 at Omicron could be notated as a different time on 12/25 at Tau, and some time on 12/27 at Phi could be notated as a different time on 12/26 at Tau. Another possible explanation, if the errant time is at Tau itself and not at the climber is that it took a while to cross the abyss, after all, Pederson said "We're having a really tough time with this sector" during a radio call to Tau while in the Omega Sector.