Parallel
Numbers 10:6
Brenton's English Septuagint · Berean Standard Bible
And ye shall sound a second alarm, and the camps pitched southward shall move; and ye shall sound a third alarm, and the camps pitched westward shall move forward; and ye shall sound a fourth alarm, and they that encamp toward the north shall move forward: they shall sound an alarm at their departure.
When you sound the short blasts a second time, the camps that lie on the south side are to set out. The blasts are to signal them to set out.