Let me start by asking why you want to update them? Will you be doing extensive editing over many new editions? If not, I'd seriously consider leaving them in CS5.5. Updating the files can have some nasty text reflow surprises due to changes in the text engine. The surprise part comes from the fact that the text won't recompose until you actually touch it in some way, or foce the recompose. You might not see the changes in a long doc until it's too late and a page break has moved or some chapter is overset.
Thanks for pointing this out. I had no idea.
The reason (which may not be valid) I wanted to update them is I wish to redo the way the book is set up so I can easily export it to digital book formats. I gather that's going to require rethinking the way I have done the headers and footers (moving them to different layers or conditional text or something along those lines) so that I can make sure they are not incorporated into the digital version (which, as you likely know, reflows the text).
But from what you are saying, I gather I should just make my changes and then select 5.5 as the version when I resave each file.
Have I understood you correctly?
I should add, however, that at some point in the future one of these books will go through a major revision. In that case I will in fact be changing a significant amount of the content. At that point I get the impression it would be good to convert the whole book to CS6. Or is that also not correct? I am assuming there are features available in CS6 that will require the book being in CS6 format if I am to take advantage of them. Have I understood that correct?
I appreciate your knowledge on this.
I think that's a valid reason, actually.
My inclination would be to use a script to convert the files in CS5.5 to .idml. then open those (tedious, I know, but the trip through .idml will force the recompose) and resave as .indd in CS6, check them carefully (there are scripts for finding oversets, but I'd still do a visual check for bad breaks and such), then make new Book files.
I recently found two scripts for doing the initial conversion. One is by Kasyan Servetsk and the other is by Peter Kahrel and available on his website: http://www.kahrel.plus.com/indesign/batch_convert.html
I think Peter's script can be used to convert directly from CS5.5 to CS6, but I'd do it in two steps. You could probably batch conver the .idml to CS6 .indd using the script, too, to save some aggravation, but that won't remove the need to check things.
Thank you Peter. I have taken a look at that script and I am about to give it a try. It looks like it will be VERY handy, and exactly what I was looking for (a way to automate this process).
I'll post back with news on how I get on with it.