If you read my previous post you can use this as an update.  The same number called me back just a few minutes ago.  It is a outbound phone number from Dell Technical Support.  They are calling and giving updates to people about the ETA of replacement parts.

Someone from this number called me at 2:47 PM EST on 3-24.  I was unavailable at the time of the call so I rang it back when I was able.  I received a message from an Indian speaking representative telling me the number was no longer being used and to call this number - 877-800-8018
When I call that number it gives this message "The number you have dialed cannot be reached from your calling area" then the line disconnects.

called at midnight 3-13, didn't hear a disconnect, but no one said anything.