setPostalCode Doesn't Work With Single Element Form

I followed the documentation on setting up the Single-element payment form, and as I already have the users post code I’d like to pre-populate it to make the process easier. However, I’ve added the following code as per the docs but although the callback executes, the post code isn’t set in the UI.

paymentFormLoaded: function() {

Responded in this thread: Change placeholder text on card element to be Postcode instead of ZIP, but basically it currently is not supported in the single-card element unfortunately.

These are actually two separate issues. The other one was about replacing the ZIP placeholder text, but this one is about actually setting the post code value.

Ah, sorry, I totally misread. That, unfortunately, is also not currently possible.

The single element form really isn’t much use then.