Images from tv and movies come to mind - of the Kurdish peoples of Iraq/ Kuwait, of caravan camps in the Middle East and United Kingdom, of people walking around in the middle of nowhere in Africa.
I think it would last for exactly as long as the circumstances that forced the upheaval, then immediately begin to settle. Like a jar full of water and sediment: as soon as you stop shaking, the pebbles will lay still on the bottom.
It's a hard scenario to picture, because there has never been a time in human history when -globally- people just up and move all at once. Settling is natural. Movement is usually by necessity. Even in a culture that honors the necessity of movement (due to climate or hunting migrations) there is long term settlment bound into the lifestyle. The need to stop is equal to the need to go.
It's fun though, to picture a caravan of limousines circling for the night to secure their wealthy travelers.