Numbers 10:6

Good News Translation

When short blasts are sounded a second time, the tribes on the south will move out. So short blasts are to be sounded to break camp,

See the chapter Copy

Next, those under the banner of the division led by the tribe of Reuben would start out, company by company, with Elizur son of Shedeur in command.

but in order to call the community together, long blasts are to be sounded.