“the tenth day of the first month.” The 10th day of the first month, Nisan, is the day that the Passover lamb is selected (Exod. 12:3). That means it had been almost 40 years to the day that Israel left Egypt, because they left on Nisan 15, forty years before (Exod. 12:29-40).
“on the east side of Jericho.” No evidence for this camp has ever been found.