Numbers 9:19

And if the Cloud tarried over the Tabernacle many days the children of Israel observed the watch of the Word of the Lord, and did not proceed.

AND WHEN THE CLOUD TARRIED. This means that if the cloud tarried upon the Tabernacle many days, and the place [where they happened to be camped] was not good in their eyes, so that they very much desired and wanted to journey away from there, they were nonetheless not to transgress the will of G-d; this being the meaning of the verse, and the children of Israel kept the charge of the Eternal, and journeyed not, namely that [it was only] because of their fear of G-d and because they kept the charge of His command that they did not journey. Similarly, if the cloud was there only a few days, for instance two or three days, and the people were very tired because their strength had weakened in the way, they would nonetheless fulfill the will of G-d and walk after the cloud. And Scripture further relates that sometimes they tarried for only one night and journeyed in the [next] morning, although it was a great strain for them. And at times the cloud tarried a day and a night, when they had journeyed throughout the night and arrived at that place in the morning, and the cloud stayed there all that day and all the night, and was taken up on the second morning and they journeyed. This was an even greater trouble for them than the previously-mentioned one, because the people would think that they were to stay there [for a long time], and would unload the wagons and lay down their burdens, as is the custom of those who come from a journey, and when the cloud was taken up they began reloading, and could not make any preparations for the journey. Whether it were two days, and they journeyed at night.
It is possible that it happened during their journeys that they had to do as is narrated here, and not in another way, namely that the cloud first tarried from evening until morning, then a day and night, then two days, then a month and finally a year. This is why Scripture mentioned these periods in detail. It [the cloud] would also tarry for many years, as Scripture mentioned at the beginning [of this section],, which means “many years.” such as in Kadesh of which Scripture states, And ye abode in Kadesh many days, according to the days that ye abode there.).

. ושמרו בני ישראל את משמרת ה', the reason why the Torah repeats this fact a second time is to emphasise that even when the location selected by the cloud was not only inhospitable, but the cloud remained there for a long period, the Israelites did not grumble or protest this fact. They did not start journeying on their own, looking for a more suitable place to encamp.