kindle, plugboard, series & renaming existing books

hi,
I found out how to use the plugboard thanks to this website : http://www.howtogeek.com/114063/how-...-ebook-series/

that said it's apparently in the stickies here too xD

Anyway, the point is :
this works fine
but I have existing books which are on the kindle for which I synchronized the metadata but who are named using the old name template
so they don't contain the "Series-xx-bookname" but just the bookname

is there a way to update this while keeping the lastread page ?

I fear deleting & reuploading it from the calibre library would fix the naming template but would probably delete the reading progress right ?

Thanks.