Arrange Coverage for a Conflicting Saturday Shift

You work at Birch Lantern Homewares and are scheduled from 9 a.m. to 5 p.m. this Saturday. Your sister needs your help moving that morning, but you can reach work by noon. Your colleague Owen can cover 9 a.m. to noon if you take his Tuesday closing shift. You are free on Tuesday and trained to close the shop. Manager Leena Marsh must approve swaps by Thursday afternoon so she can update the rota.