The problem with the date is that it doesn't fit in too well given that:
A. The Heresy broke out early in the 31st Millenium, and the siege of Terra took place, at least according to the old Bill King story, 14 years into the 31st Millenium.
B. The Great Crusade lasted 200 years, and the Index Astartes suggests Night Haunter was found towards the end.
The Cherault date is given in the Official Imperial System (see
here) so is in the year 29,826.
So if the date is correct, this means Kurze fought Dorn and went AWOL over 170 years before the Heresy broke out. Given that based on the novels the period between the end of the Great Crusade and the outbreak of the Heresy was measured in years rather than decades, this would place Kurze's dissapearance early in the Great Crusade, which seems highly unlikely - first of all because it seems he was found later in the Great Crusade, and second because this means after 170 years of rampaging around the galaxy indiscriminately slaughtering planetary populations he had still not been declared a traitor, and had only just been summoned to return to Terra and account for his actions (seeing as this occured just before the Heresy broke out).
I reckon that particular date should be treated with a hearty amount of scepticism personally.
This post has been edited by The Red Sorcerer on Nov 3 2009, 11:24 AM