When I edit the charge policy of a product, why can my changes only become effective on the following day?
ContactsLaw does not permit more than 1 charge policy to come into effect on a single calendar day.
If you wish to edit a product multiple times in one day and have the changes effective immediately, you must first delete that day's product history. Product history should not be deleted for previous days (except to correct errors).
Once this is done, from within the charge policy tab you can choose to have your changes take effect from the date of the change.