JS Post Code Check Not Working

Hello, it looks like the the javascript for checking the postcode in the checkout for location based rules does not work for guests (it seems to work okay for logged-in users). To clarify, I am referring to the checkout updating when data is entered into the postcode field at checkout then the input field is ‘unfocused’ (user clicking outside of the field after data entered) the checkout does not update to show the correct shipping method (if shipping rule is correct for that postcode). Note: it does work when you force an AJAX refresh by ticking and unticking use shipping address so the conditions are correct but this is not ideal and is greatly affecting user experience and causing issues when purchasing. Please can you confirm if this is an issue with the current version of the plugin and when this will be fixed? Thanks, Stuart