Right now the choices for a list custom field can only be set directly on the custom field settings. This is nice to use as default choices for the custom field. However, some use cases require that the choices be different. For example, I used a custom field to set the available times for a recurring event. Most of the days the available schedule are the same, so having the choices set in the custom field works. Other times, however, the schedule changes, so the choices for available times should change, too. This can be accomplished currently by creating a duplicate of the custom field, altering the available times, and then changing the visibility of the field so it only appears on specific events. This is a bit cumbersome and will require creating a custom field for each set of available options.
