Unless it's a direct to print, vanity press type of thing, you can be rather sure the publisher would hate you for using .pdf.

What they're likely to want is a non-formatted text-only format that can be easily edited to fix your spelling and grammar mistakes, and can be broken up in pages based on their decisions on fonts and page sizes.
Possibly one with functional rather than layout based markup.

They definitely don't want you to force the layout decisions, especially for something that might be published in different layouts.

Converting from .pdf is a hellish nightmare compared to a clean textbased markup format.

__________________
‘To those who regard “crime fiction” as some sacred icon which must follow a rigid formula, I will always be the man who writes 18-syllable haiku.’Trying to make sense of computers, The Error Log.