When I got my V6 box, I kept the old tivo box as well.
I copied the series links over and made it the default box. When the V6 got full, I did the reverse and made the tivo the default box. Now, the tivo is full and this is the problem and contradiction I made the V6 the default box, and copied the series links over ( but there was no confirmation that it had been done successfully – if there is a confirmation )
The images below suggest that the V6 is the default box while also suggesting the V6 is the “ other box,ie not the default “ It hasn`t worked because all of the planned recordings are going to the tivo.