I received this update from QuickBooks a few minutes ago.

Thank you for your continued patience while our engineering team looked into this issue for you on QBOP: error with rep ID - Unable to upload T4, T4A, T5018 .xml file.Please note that we are working with CRA to have this issue resolved. In the meantime, here are three potential workarounds to resolve the issue:

1. If you have access to your client's My Business Account (MyBA), you can log in and upload the file directly.
2. Alternatively, send the XML file to your client and ask them to upload it through their MyBA account.
3. As a final option, you can edit the XML file. To do this, open the file in Notepad, locate the "” tagline, and insert the following information directly below it:

     xxxxxxx

Replace the ‘xxxxxxx’ with the 7 alphanumeric value that’s equal to their Representative Identifier.

Note: Please ensure there is an indent for  xxxxxxx to align with the
XML document.

Thank you for your continued patience while we worked towards completing this investigation.

This is in reference to support contact Case Number 15129952901. 

Sincerely,

The QuickBooks Team

Can anyone make sense of this?