Day files on several days. One file (a run packet, a tech pack, a parking map) can show on every day it covers, so you upload it once.
ADDING: on a day's Files tab, pick the file. Under Show on the day you are on is already checked; tap the nearby days (3 before to 2 weeks after) to add them, then save. The file's line then says which days it is on, like Nov 1 to Nov 5 (5 days).
CHANGING THE NAME OR TAG on any of those days changes it on all of them.
REMOVING: the trash button on a file that is on several days asks: Remove from this day (the other days keep it), Delete from all N days, or Change days to pick the days again. A file on one day is just removed.
WHO: the same people who can add and remove day files on one day. Each day still decides who sees its files.