Factual error: The satellite phones don't work as they should. They're somehow still able to use them to communicate after the moon has got close enough to the earth to cause enough damage to the satellite network that it'd no longer function, and can also make and receive calls while under tons of rock.
Factual error: In one scene, Winifred asks Gilbert who Trask is and Gilbert replies that Trask is the "mayor", to which Winifred just acknowledges. However, the office of mayor was not created in Massachusetts until 1823, which is 130 years after they were hanged, so given the witch's lack of knowledge of the modern day, she would have likely not known what Gilbert meant.
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