USAS and USPS integration takes place automatically within MCOECN Hosting. There are Kubenetes services that run that allow them to communicate behind the scenes. There is no longer a need to edit any settings in System....Configuration....USPS Configuration (within the USPS application GUI) or System...Configuration...USAS Configuration (within the USAS application GUI).
If you do go to USPS Integration...Security Configuration within the USPS application GUI (or USAS Integration...Security Configuration within the USPS application GUI) and click Generate API Key, this could break integration for MCOECN hosted deployments. The presence of this key will cause it to be used instead of the Kubernetes services. This is pretty easy to fix...just click Disable Message Security and the API key will be removed, and this will allow the Kubernetes services to talk directly again.
If you still have issues, contact the MCOECN DataCenter team at dco@mcoecn.org.
