Comment by kaosmos

In your story I can find a similarity with a problem I had: you were put on hold because of a "key customer" while I haven't enough "bargaining power" to have my customer to stop the former website from receiving new orders and new registrations (it is an ecommerce website) for a time long enough to have the site correctly migrated without further pressure. In both cases there were an added difficulty because of being too much "compassionate" with the customer needs.