fg_entryautomation_after_export.php

<?php

add_action( 'fg_entryautomation_after_export', 'fg_entryautomation_remove_header_row', 10, 3 );

/**
 * Remove header line from generated CSV export file.
 *
 * @param array  $task      The current Entry Automation task's settings.
 * @param array  $form      The current Form object.
 * @param string $file_path File path of export file.
 */
function fg_entryautomation_remove_header_row( $task, $form, $file_path ) {

	// If this is not a CSV export, return.
	if ( rgar( $task, 'exportFileType' ) !== 'csv' ) {
		return;
	}

	// Get the file.
	$file = file( $file_path, FILE_SKIP_EMPTY_LINES );

	// Remove the first line.
	unset( $file[0] );

	// Remove empty items.
	$file = array_map( 'trim', $file );
	$file = array_filter( $file );

	// Convert file back to string.
	$file = implode( PHP_EOL, $file );

	// Save file.
	file_put_contents( $file_path, $file );

}