I have stamp in my passport that says admitted until 10 MAR 2017
Does it mean that I have to leave before 2017-03-10T23:59:59 (country I am in timezone), or I have to leave before 2017-03-09T23:59:59? (before day I am admitted until starts)
For bonus points, what if my flight is on +1 day but I go through customs day before while my visa is still active and spend it in departure hall?