Cheers Oxburger, panic is over. Just had a Sales twat not know anything and made me jump through a hope, if you know what I mean.
Surprisingly (?) after talking to the printer, Sales twat says I'm right. Imagine that... I have just managed to save one of my staff trying to impose 48 pages with a single page back up. Naturally saving the company a pile of cash and time so that we could get on with the 'next bag of thing' has done nothing for my reputation.
I find myself working for an Agency ruled by Designers who have little clue. And something called 'Process' is a mystery to them.
Rant over

Thanks again