Hi @tommy,
strangely, when re-testing the auth process again today, I started receiving the mismatch error with my workaround in place. I have now removed that and all is behaving correctly. I have no good explanation for what went wrong previously - can’t even think of any sort of caching issue that may have been the culprit, but I think we can put this one to bed anyway.
Much appreciated on the documentation follow-up!
Kind Regards,
John