This from the Detriot Free Press:
Dec. 8 — “Safe Harbor” deadline
The Electoral Count Act, which Congress passed in 1887, contains a “safe harbor” clause that frees a state from further legal challenge if it certifies its election results at least
six days before the state’s electors meet. That means that if the state issues a final tally of the votes cast in its presidential contest by Dec. 8, 2020, Congress is required to accept the state’s electoral votes. If legal disputes remain
unresolved, Congress
could decide which slate of electoral votes to count.