Hello Dennis.

You can try using the following script:

<script>
 function getUrlVars() {
   var vars = {};
   var parts = window.location.href.replace(/[?&]+([^=&]+)=([^&]*)/gi,   
   function(m, key, value) {
     vars[key] = value;
   });
   return vars;
 }
 bookingEntitiesIds[bookingEntitiesIds.length - 1]['service'] = getUrlVars()['service'];
</script>

Here's also an example of changing the Employee's ID with the help of some plugin which has the possibility to use PHP Snippets, and add shortcodes on the page in that way. For example:

1. There's the page (where you want the booking form to be), and when you're creating links that lead to that page, in URL you need to place the ID for the employee (http://somesite/booking?employee=17)

2. On that page (where you want the booking form to be), instead of our shortcode, you'd need to add the shortcode of that plugin which uses PHP Snippet which will generate our shortcode (https://wordpress.org/plugins/insert-php-code-snippet/).

3. The snippet would look something like this:

<?php
$employee = $_GET['employee'];
echo do_shortcode( "[ameliabooking employee=$employee]" );
?>

I'm glad to hear that, Dennis!

If you have any further questions or issues, please feel free to open a new ticket, and we'll gladly help.