I received a response informing that the issue in this thread related
only to the test environment and is now resolved. I'll follow up here if
I can find out any more about similar issues in the live environment.
I am also seeing this issue at a customer site. The relay response POST
is not received. This is with live transactions, so the user's card is
charged but no action can be taken due to the POST not arriving. The
core problem is that the POST does not...