Filters the discount code generated in Subscriber Discounts for WooCommerce

functions.php

add_filter( 'sdwoo_discount_code', 'custom_subscriber_discount_code', 10, 2 );
function custom_subscriber_discount_code( $final_code, $email_address ) {
	// Start a new discount code.
	$new_code = '10OFF-';
	
	// Maximum length of the random string of characters after the new code.
	$max_length = 4;
	
	// Choose a random starting point to shorten the string to help avoid repeated strings.
	$rand_start = rand( 0, 6 );
	
	// Retrieve x = $max_length characters from $final code using a random starting point (0-6).
	$shortened_sting = substr( $final_code, $rand_start, $max_length ); 
	
	// Combine the new code with the shortened string.
	$new_code .= $shortened_string;
	
	return $new_code;
	
}