You can use either acf/load_field https://www.advancedcustomfields.com/resources/acf-load_field/ or acf/prepare_field https://www.advancedcustomfields.com/resources/acf-prepare_field/. I would go with acf/prepare_field. In the filter check the role of the current user and if not an admin then set `$field[‘readonly’] to false. The page you refereed to is moved to here https://www.advancedcustomfields.com/resources/acf-load_value/
