How to update Vue component props after instance is created

Let’s say I have component class

const ComponentClass = Vue.extend({
  props: ['myProp'],
  template: '<span>Hi {{myProp}}</span>'
});

Then I create new instance and mount it

const instance = new ComponentClass()
instance.$mount('#myApp')

How can I update prop myProp?

After instance is created prop can be just updated like other data properties. You can update is like
this.myProp = newValue of what ever you want . But you have to do it in that component to whom props are passed.