I'm assuming that your checkMyForm() function is in effect your check_promisLot() function, you should change that.
Have you tried clearTimeout, it would go something like this;
var delayExec;
function check_promisLot () {
clearTimeout(delayExec);
var input = document.getElementById("myInput");
var form = document.getElementById("myForm");
if ( /* check the input here */) {
delayExec = setTimeout(function() {
// submit the form
$("#myForm").submit(); }, 1250);
}
else {
// do nothing
}
}
Essentially, try to reset your timer every time an update triggering event happens.