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A quinta temporada é executada entre:
February 1984 and August 1984, shown by the reference to the TV broadcasts of the 1984 Winter Olympics in episode 1 and the coverage of Ronald Reagan's "We begin bombing in five minutes" joke in episode 13.
Considerando que Temporada 6 ...
The events of the sixth season begin in late September 1987, three years after the conclusion of season five.
Do episódio 1 daquela temporada ..
Elizabeth is exhausted and resentful from handling a full KGB case load nine weeks before the Reagan-Gorbachev summit...
... que aconteceu de 8 a 10 de dezembro de 1987
Então 3 anos seria correto.