For the points 1 and 2 there is a solution but tested
1. automate the survey to be available online at a set date and time
2. automate the survey to NOT be available online after a set date and time
You can use an structure in index.php to redirect the survey if the variable sid is your survey target and time is your time needed
something like this :
define your time
if ($_GET['sid']=='19456'

{
{
if ($my_time < gettime()){
do nothing
}else{
header("Location:http.yoursite.com/survey_page_closed.php"

}
}