In that case I would look into adding a repeater field render field area and adding a custom update_value and load_value methods that saves the “value” of the field based on this other field and returns an array from the field. Basically, you need to use a repeater field for the field value. However, if you want to add a “value” and the repeater, that would be an issue unless you built some custom way to store both values because ACF can only store one “value” per field.
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