Hi Dan,
I think you have a typo on this page
http://blog.daypilot.org/2009/11/scheduler-time-line-scale-options.html
You say that the following:
CellDuration="10800" CellGroupBy="Month"
But if a calculate the CellDuration of a week
60*24*7 = 10080 and not 10800
Greets NeokGlitch