public function sanitize_email_address( $value ) {
		$value = trim( (string) $value );

		// Allow user to unset by providing an empty string.
		if ( ! $value ) {
			return '';
		}

		$new_value = sanitize_email( $value );

		if ( ! $new_value ) {
			add_settings_error(
				'soter_email_address',
				'invalid_soter_email_address',
				sprintf(
					'The email address provided [%s] does not appear to be valid.',
					esc_html( $value )
				)
			);

			return $this->email_address;
		}

		return $new_value;
	}