I am the happy owner if GUB (Glashütte) Ship Chronometer. It came with its most recent test and re-calibration statement from the calibration authority of the German Democratic Republic.
That document dates to March 1990.
So while the Warshaw pact had broken down, Soviet and GDR governments and political systems turned over, while the two German states were negotiating their reunification, there were people who did what had to be done: Calibrating mechanical ship‘s Chronometers. Because these were still being used in day service.
And even today there are still ships that carry a mechanical Chronometer for backup reasons.
I love the thought.