I've re-named all the books "Astounding Stories - [date]". That should help ID them. I didn't do it before because they were all in an "Astounding Stories" folder on my computer/Calibre/PB360. So,
I knew what they were ... !
I don't believe it'll muck up MobileReads files because the ebooks are sorted by the thread title, which I have not changed.
Marilyn