Special Elections; Requiring that a written resignation be submitted by an officer within a specified timeframe if such officer is filling a vacancy caused by a certain resignation; providing construction; revising the timeframe during which a vacancy that occurs in an elective office must be filled by candidates qualifying within the timeframes provided by general law; requiring the Governor to fix the dates of the special election within a specified timeframe after the vacancy occurs; requiring the Governor to fix dates to coincide with an already scheduled election; requiring that vote-by-mail ballots from overseas voters be received before a specified time on election day, etc.