The only converted 747s with the distinctive double row of windows in military use are the Air Force One and E-4 aircraft I already mentioned. Neither of which is going to be anywhere near Soviet airspace without the Soviets knowing long, long in advance.
I also quoted the pilot himself. Further from him:
> "I was just next to him, on the same altitude, 150 meters to 200 meters away," he recalled in conversations with a reporter during the weekend. From the flashing lights and the configuration of the windows, he recognized the aircraft as a civilian type of plane, he said. "I saw two rows of windows and knew that this was a Boeing," he said. "I knew this was a civilian plane. But for me this meant nothing. It is easy to turn a civilian type of plane into one for military use."
It wasn't a "oops we thought it was an RC-135" scenario.
I also quoted the pilot himself. Further from him:
https://www.baltimoresun.com/news/bs-xpm-1996-12-09-19963440...
> "I was just next to him, on the same altitude, 150 meters to 200 meters away," he recalled in conversations with a reporter during the weekend. From the flashing lights and the configuration of the windows, he recognized the aircraft as a civilian type of plane, he said. "I saw two rows of windows and knew that this was a Boeing," he said. "I knew this was a civilian plane. But for me this meant nothing. It is easy to turn a civilian type of plane into one for military use."
It wasn't a "oops we thought it was an RC-135" scenario.