Auto update books already on device?

I use Calibre with the Kobo Vox and have all my books stored on it, used the Calibre send to device option on it (stored on internal sd card).

I have noticed that some of my books have slight format errors so have done a reconvert of them, when I next connect up my Vox will these changes automatically get transferred across?

or will I need to remove books from device and then re add them

Thanks