I had a partially defective Tivo that needed to be replaced with a factory renewed Tivo. I probably had 30 Season Passes to transfer.. But, since TiVo takes the liberty to transfer the lifetime service to the new box from the old when it ships instead of waiting until I receive and install, it made it impossible for me to transfer the SPs. TiVo needs a better solution to that. Not to mention, that my partially working Tivo that was being returned had its service terminated several days before I actually got the new one. That's a poor procedure as well. TiVo should not active the new service until I receive and activate the factory replacement.
It would be cool to ask me during the activation of the new one if I wanted to auto transfer all the SPs from the box being replaced.. that would be the best way to do it. It' all just some code writing on TiVo side.