Numbers 9:20-21

20Sometimes the cloud remained only a few days over the tabernacle, and in accordance with the command of the Lord they remained camped. Then at His command they set out.

21If sometimes the cloud remained [over the tabernacle] from evening only until morning, when the cloud was lifted in the morning, they would journey on; whether in the daytime or at night, whenever the cloud was lifted, they would set out.