Beginning 16th March 2017, we have seen that British Telecom is deferring some email messages that we are attempting to deliver to BT’s mail servers. This may impact messages sent from our UK-based customers to domains that are hosted with BT. We have been in conversation with BT as to the cause of the deferral, and are pushing for a resolution from them. In parallel, we are also exploring potential workarounds to the issue, although the full resolution will likely need to be provided by BT.
We are continuing to work on this issue and will provide updates as they become available. We appreciate your patience as we work to resolve this matter.