Before opening the Deep Winter writs for the Rough Box, Boarded and Rough Crate, Reinforced they both indicate 1 item but after you accept them they show 12 items are required. Other multiple item festival writs, such as the military stretcher, tell you correctly before you accept them how many items you will need. All of the Deep Winter Charity writs should indicate how many items they will require before accepting them or the required item count should be set to one.