I have set up a Gantt chart where everything has a duration of a whole number of years (starting January 1 and ending December 31), and the categories are the years (likewise starting January 1 and ending December 31 - data XML is attached). The task bars should line up with the category boundaries, but as can be seen in the attached screen shot, they are all shifted to the left by what appears to be about a month.
Gantt1.xml