Listen to custom events and call purge

wp-graphql-smart-cache-custom-even-listener.php

add_action( 'graphql_cache_invalidation_init', static function( \WPGraphQL\SmartCache\Cache\Invalidation $invalidation ) {

	add_action( 'updated_option', static function( $option, $value, $original_value ) use ( $invalidation ) {

		// phpcs:ignore
		if ( ! isset( $_POST['_acf_screen'] ) || 'options' !== $_POST['_acf_screen'] ) {
			return;
		}

		// phpcs:ignore
		$options_page = isset( $_GET['page'] ) ? $_GET['page'] : null;

		if ( empty( $options_page ) ) {
			return;
		}

		$invalidation->purge( 'graphql:Query', sprintf( 'update_acf_options_page ( "%s" )', $options_page ) );

	}, 10, 4 );

});