How to update Ember.binding from when bound property updates on component

I have a simple component that on init binds a custom computed (as the lookup is dynamic based on the index passed in)

export default Ember.Component.extend({
    tagName: "span",
    classNameBindings: ["visible"],
    attributeBindings: ["className", "index", "field"],
    visible: function() {
        return; //apply some logic here
    }.property("validationIndex"),
    initialize: function() {
        var field = this.get("field");
        var index = this.get("index");
        var validationIndex = "targetObject.%@1%@2Validation".fmt(field, index);
Ember.Binding.from(validationIndex).to("validationIndex").connect(this);
    }.on("init")
});

The question is, when the each loop has an item removed (from the ArrayController essentially) .. how can I update the binding to reflect this new one?

Thank you in advance