Contact Form 7 (3.8) - change recipient based on zipcode

cf7-plugin.php

<?php
/*
Plugin Name: Contact Form 7 Zipcode check
Plugin URI: http://youruri.com/
Description:
Author: 
Version: 1.0
Author URI: 
*/

function prefix_zipcode_check (&$WPCF7_ContactForm) {

	$form_id = $WPCF7_ContactForm->id;

	// Check if it is the correct form
	if ($form_id === 1) {
		
		// Replace ['zipcode'] with the correct fieldname
		$zipcode = $WPCF7_ContactForm->posted_data['zipcode'];
		
		// Remove all characters other than numbers
		$zipcode = preg_replace("/[^0-9]/", "", $zipcode);

		//Access the correct property, which is form in this case
		$recipient = $WPCF7_ContactForm->mail['recipient'];

		//Sets the correct recipient value (e-mail adress) for each ZIP code range
		switch($zipcode) {

			// Recipient 1
			case $zipcode >= 1000 && $zipcode <= 1499:

				$recipient = "Recipient 1 <recipient1@domain.com>";

				break;

			// Recipient 2
			case $zipcode >= 1500 && $zipcode <= 1999:

				$recipient = "Recipient 2 <recipient2@domain.com>";

				break;
			
			// Default recipient
			default:

				$recipient = "Recipient default <recipientdefault@domain.com>";

		}

		//Sets the property for the recipient with the variable defined in the switch statement above
		$WPCF7_ContactForm->mail['recipient'] = $recipient;

	}

}

add_action("wpcf7_before_send_mail", "prefix_zipcode_check");