AngularJS : ng-model binding not updating when changed with jQuery

Angular doesn't know about that change. For this you should call $scope.$digest() or make the change inside of $scope.$apply():

$scope.$apply(function() { 
   // every changes goes here
   $('#selectedDueDate').val(dateText); 
});

See this to better understand dirty-checking

UPDATE: Here is an example

Just use;

$('#selectedDueDate').val(dateText).trigger('input');