In BlockSurvey, you can easily set up your survey or form to auto-close based on a specific date and time.
Go to Settings -> Response Management and enable Autoclose / cut-off date to set the date and time you want the survey or form to close.
Note: This uses your local timestamp to set the auto-close date. It's stored as a UTC timestamp and works perfectly for respondents in all timezones.
Give it a shot and see how it works!