I think I will leave the date on which the documents were created; that will be the safest bet. That will be for both the name of the file, and inside the guide.Thanks!
Perhaps don't bother changing the date to match the update's date? Either leave the date on which the documents were created, or leave out the date entirely. Or put the date on the filename, not inside the document, then I can change it (if I remember!) when I upload the update.
You will find the updated files in my previous post soon enough.