Okay, obviously this is only a guess (albeit somewhat informed since my guess above was on the nose) - sounds like it is in Warsaw and somebody 'did something' with the file, like formally put it in the queue or assigned it to someone. Hence the language that seemed to go backwards to 'when we start your background check'. (I find the messages confusing because in reality there are several different actvities under 'background check'.)We passed medical end of November. Biometrics sent at the same time. This is the first change/update since that time.
Possible next step - if warsaw still doing things as before - might be AOR2.