A "shift" consists of one 4-hour block of time.

Work 1 shift: Shop at 2:00 PM on Thursday

Work 2 shifts: Shop at 1:00 PM on Thursday

Work 3 shifts: Shop at 12:00 PM on Thursday

Work 4 shifts: Shop at 11:00 AM on Thursday

Work 5 shifts: Shop at 10:00 AM on Thursday

Work 6 shifts: Shop at 9:00 AM on Thursday