A month ago to the day, I handed in the "final" draft of my book to my editor.
I've never had anything be "final" before in my life. I have dozens of drafts of dozens of projects hanging around in my hard drive. I tend to skip around a lot from project to project - especially in between drafts - as a good way to keep myself sane. Usually that means I'll open up the latest draft of project X and start tinkering with it, while I give the second draft of project Y a month or two to cool off before I reread it and tinker some more.
Before I handed in my manuscript, I counted how many drafts of it I had on my computer. There were 26. Some drastically different than the one before it, others with only minor phrasing changes. But the fact that there will probably never be a 27th draft of this project, that once it's published I can't tinker with it anymore (well, I can, but only for the benefit of my hard drive and my neuroses) is totally surreal.
I know I'll have a couple more chances to read the book before it's really, really final. Right now it's with a freelance copy editor who is reading it afresh and who will help to catch and fix any remaining typos, grammar and continuity issues. And then I will get a final version to read when it's typeset and looks like a real book. I think I'll be able to change a word here or there if absolutely necessary. But will I be able to completely overhaul major plot points and introduce kooky and lovable secondary characters? My educated guess is that my editor will say something like, um, no.
I'm living in the Twilight Zone, people. What if the 27th draft is THE ONE?!
Actually, that might be a good idea for a Twilight Zone spec script. Maybe I'll go work on that...