How to export custom post type with ACF to individual file with automation?

Schedule your backup with WP Cron – https://codex.wordpress.org/Function_Reference/wp_schedule_event

In the cron event, run your query for posts or CPTs and be sure to add 'numberposts' => -1, to return all.

When you loop through your posts from the resulting query, push the values to an array $data[]=$some_string_data_for_prop;

And when you’re ready to write the data, convert the array values to a single string; $output = implode("\n", $data);

Then write the data to a file file_put_contents($filepath, $output);

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