During the recent supply chain disruptions, the "dwell time" of shipping containers $($the time elapsed from when the cargo arrives at the port to when it leaves the premises$)$ at the Port of Los Angeles has been increasing.$$ There are currently $11$ thousand shipping containers arriving every day.$$ The Port Control Tower regularly counts the number of containers at the port $($which covers all steps of the process described below$).$ Over the last six months this has averaged $274$ thousand containers.

Processing containers involves several steps.$$ First the containers are unloaded from the ship $-$ taking an average of $1\mathrm{.}5$ days.$$ Then there are customs and safety inspections taking an average of $3$ days.$$ Then containers wait in a container stack until the receiving company is ready to pick it up$.$ Finally, the container is loaded on a truck or train, taking $0\mathrm{.}5$ days.

The Port Control Tower believes that the increase in dwell time has come primarily from the time containers spend waiting for pickup.$$ Given this information, what is your best estimate for the average number of days a container spends waiting in a container stack during the last six months?