ITMS 8.6 RU2
These messages are trace level and internal. Our process is just trying to identify different types of Installation Files
Those messages are by design for now. Those are logged as trace (these are not errors /warnings). These messages are not impacting functionality. The customer should ignore those messages as they are trace level, not an error.
When a package is importing, our code tries to understand what package we have and tries to parse file for different installation file types, ding it one by one until type is found. If type does not match, it writes trace to log saying that "type is not matching because package is not valid XML". When type matches, it does not write anything to log. That's why we see those messages - it is just one of attempts to identify package installation file type.