title: Apple says "Your iOS Distribution Certificate expiring" what i need to do
body: <p>I got this mail from Apple.</p>
  
  <blockquote>
    <p>Your iOS Distribution Certificate will no longer be valid in 30 days. To generate a new certificate, sign in and visit Certificates, Identifiers &amp; Profiles. </p>
  </blockquote>
  
  <p>I get some information from <a href="https://stackoverflow.com/questions/10759973/proper-way-to-renew-distribution-certificate-for-ios">StackOverFlow</a> but I want to know what I need to do if I modify my existing app. Will I able to update in future the same app with new certificate and new profile. Is that I need to revoke and generate the new certificate. Thanks for your help and comments.</p>