"Replace Landing Page" action

Since you can't change the template used by an existing landing page, it would be great to have a landing page action that would allow you to replace all instances of a selected landing page with a new landing page.

For example, "landing page A" uses free form template, and you want to this landing page to now be responsive. So you create "landing page B" with the same content, but it uses Guided template.

Now you want to be able to tell Marketo wherever "landing page A" is mentioned in smart lists, replace that with "landing page b". And have "landing page b" take over URL used by "landing page a".

This would prevent any smart lists and resulting smart campaigns from breaking when migrating to a new responsive landing page.