A slight modification has been made to the way in which invalid expiry dates are handled.
As the ability to set the expiry date/time is a new feature to our SMS API, it was initially decided to ignore invalid values that may have been provided. However, in the response of valuable customer feedback, it has now been decided to fail broadcasts which have invalid an expiry date/time.
This is because clients who are setting the expiry date/time have a reason to and our ignoring it (when provided in an invalid format) might cause harm to the intended use of the client.