[tobyg]

So this seems to work for a single post ID, how can I generalise out for all posts in a specific custom post type?

    function update_acf_datetime_field() {
    // Assuming you have the post ID and your ACF field name
    $post_id = 120;  // Replace with your actual post ID
    $field_name = 'date_time';  // Replace with your actual ACF field name

    // Get the current value of the ACF datetime field
    $current_datetime = get_field($field_name, $post_id);

    // If the field has a value, update only the date part to today
    if ($current_datetime) {
        $today_date = date('Y-m-d');
        $updated_datetime = $today_date . substr($current_datetime, 10); // Preserve the time part
        update_field($field_name, $updated_datetime, $post_id);
    }
}

// Call the function to update the ACF datetime field
update_acf_datetime_field();

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