We've got a fairly large customer (~400 pages) who wants to completely change their design. The problem I'm facing is that the previous design was still made in the masterpage file itself. This means multiple content placeholders with the corresponding div's around them.
The new design has to be completely made in Sitefinity (like it should) but this means that there will only be 1 placeholder in the masterpage and the rest through the layout builder in Sitefinity. I know that if you, for instance, change the id of a placeholder then Sitefinity won't be able to find out where the widgets that were located on the page should come and puts them on the top where you can't delete / drag / do anything with it anymore.
This would mean that those 400+ pages would have to be deleted, remade and the right widgets with content attached to them again.
Is there an easier and cost efficient way of completely updating the design without having to rebuild everything?