1) The RC-135 has changed its unique transponder number to 730000 (hex), an Iranian assigned code. So, the USAF is impersonating an Iranian plane.
The UK, US, and a host of Baltic countries do reconnaissance near Kaliningrad daily. They frequently/always have their transponder on, and correctly display who/what they are.
Proof? 4hrs ago:
Disguising planes and turning off transponders does not communicate intentions clearly to Iran, unless that intention is war.