When using a JQL to query for Tests with "testExecutionTests" , if the username of the user has been changed, the JQL returns no results

Steps to reproduce:

• create 2 Tests
• create a Test Execution and add both tests to it and assign one of them to user A; assign the test run too.
• go into User Management and Edit user A to a different username - this case, B
• go and search for "testExecutionTests" and use the P3 (user) - if you look for A, it will not return any results - searching for B shows a message about the username being invalid.
• the jql will return the correct value if you let the user blank ('') - only the unassigned test will show on the list

Expected behavior: 

• the jql should return the information.