zip/postal code field disappears – major issue

When trying to purchase a product, user enters their address location. When UK is selected the zip/postal code field is removed, however on submission of the form the following error occurs:

‘The zip / postal code you entered for your billing address is invalid’

…but as no field is available this is impossible to resolve.

I have spoken with Downloads Digital and they told me it is an issue with this EU plugin. I disabled this plugin and tried again and can confirm the issue is coming from this plugin. This means that anybody within the EU can purchase the products anymore.

I have temporarily implemented a hack to fix the solution (which ignores any call validate the field) but would prefer an official fix please.