I successfully filed T4 and T4A today through My Business account having both my BN15 and my repid populate from Profile into the T619 header. This was for my own firm T4s and T4As. Will try a T4 file through RAC later this week but if I run into problems I already discovered that CRA will accept the xml file without BN information, so I might manually strip it out. One difficulty I currently have is that I cannot delete the BN from the EFILE options, only change it, but given the T4 deadline is in 2 weeks I don't expect Intuit to do anything about that. Omitting it would be so much easier than having to change it for every client (and the client is not the transmitter anyway, the accounting firm is the transmitter.  ???)