I have never heard that story but it sounds like a myth. The Pe-8 landed at RAF Tealing, near Dundee and I believe it also flew to Prestwick from there. I have some notes about this somewhere.

Yep, the photographs of Molotov’s arrival definitely show Tealing airfield. They were published in Volume V of the Aircraft of the Fighting Powers series. The IWM also has film of the event.

The ORB of one of the Errol units mentions a second aircraft arriving later in the month. I have a copy of it somewhere so I’ll see what it says.

Apparently, Prestwick at this time had a Russian-speaking ATC section – presumably to assist the Albermarle ferry pilots? Source was an ex-WAAF who worked in ATC there at the time.

Best wishes
Steve P