I don't believe that "double residencies" are a problem that is confined to Florida. But even with the consistent fraud that is practiced by Dem'crats, they cannot always shift the vote sufficiently in their favor to successfully steal elections everywhere.
Shuttling back and forth to vote in TWO jurisdictions separated by a thousand miles or so on the same day gets expensive AND tiring.
IIRC it was done by using an absentee ballot in one state and voting in person in the second. The ones caught in the last election were from NY and NJ and voting in FL. You can guess the party! (A few had been successful for several voting cycles.)