We have tried this in Asterisk 126.96.36.199, Asterisk 10 and Asterisk 11.3
If we have a TCP extension where calls are forwarded to a number playing early media (e.g. wrong number playing not in service announcement) Asterisk will not recognize the early media stream. However if the extension is UDP protocol then everything works as it should. This can be easily duplicated by setting up a TCP extension and forwarding the calls to an early media recording e.g. IBM 18004267378.
This creates major issues when trying to connect with a Microsoft Lync server as they only “speak” TCP and Lync clients constantly forward their calls to their cellular phone.