GDG- "changing front to the left"

[Alan D. Brunelle]

In Kershaw's OR, he notes:

    Accordingly, about 4 o'clock, when I received orders to advance, I
    moved at once in this direction [to move upon the Stony Hill],
    gradually changing front to the left.

Imhoff, Pfanz, and Gottfried all show Kershaw (basically) starting 
roughly west of the J. Rose farm stand, in a line running a little NW to 
SE. If this is basically correct, does anyone out there know what would 
"changing front to the left" mean once they got started?

Thanks,
Alan