A: The general rule is to close the period after you finalized the last payroll with a PAY DATE in that period. Remittances are always based on pay date, not work dates.
For example if we have a bi-weekly payroll for a monthly remitter with payments to employees on June 2, June 16 and June 30th you would close the period after finalizing the payrun on June 30th (it doesn't have to be paid out yet, just finalized). The June 2nd pay date would be included in this because it is paid in June, even though the work dates are likely in May. To close the period after the run that pays on May 30th please go to ACTIONS>END OF PERIOD
For more information see this video