Can I get books OFF my iPad 3 using Content Server or Companion?
 

I have an older iPad (3), and want to get some of my iBooks off of it into my Calibri library, convert them, and then transfer them to my Kindle.

If I connect iBooks to the Content Server, can I do this?

If not, can I do this with the Calibri Companion?

Or can I only UPLOAD books to the iPad?

As far as I know there is no way to get books directly from iBooks to another device. It's purely a one way street on an iPad, i.e. you can only download books onto an iPad.

On the other hand, if these are books you actually purchased at one time from Apple, they should be in iCloud. Actually converting them to a format that kindle recognizes requires a Mac and special deDRM software.

Back in the day, iTunes kept a copy of iBook files off of your devices, just as it does music. When it did, it was easy to import those books into Calibre and convert them...