input.csv

Email Address,Shift 1 (off Tu/W/Th),Shift 2 (off Su/M),Shift 3 (off Th/F),Shift 4 (off Tu/W),Shift 5 (off Tu/W),Shift 6 (off W/Th)
alice@example.com,1,2,3,4,5,6
bob@example.com,1,3,2,5,6,4
charlie@example.com,1,3,2,6,4,5
david@example.com,6,1,2,4,5,3
eliza@example.com,1,2,3,4,5,6
francis@example.com,1,5,2,4,6,3