Die-hard -- I often call them "real" -- academics get time off to write. I left graduate school right before I'd have gotten a year of stipend in exchange just for writing without having to teach. I left my first teaching job before I had enough years accumulated to apply for a sabbatical. I wasn't tenure-line at my second so never even had the opportunity to apply. So while this year was my first opportunity to write without also being in the classroom, in fact it's not that unusual for people in my profession(s).
But for me, it's been life changing. One thing is child+book writing+full-time teaching position was too damn much. Getting rid of one of those makes doing the other two one-hundred-percent more sane. Another thing is what happens when you elevate your hobby to your career and put all of that time and energy and creativity and intellectual effort and resources and priority into something you used to just make time for and squeeze in as you could. The difference shouldn't have been nearly as surprising as it was. Teaching full-time, reading and lesson planning, grading all those papers, e-mailing with all those students, commuting, working with colleagues, dealing with all the crap that comes with any job...putting all that time and energy into writing instead makes for a lot of time and energy put into writing. Basically, I wrote the whole of Goodbye For Now between June and September. People think that's mind-blowingly fast, and it is (and was only possible because I'd worked on it the previous summer and had it all planned out and ready to go in my head), but also, put 40 or 50 hours a week and all your creative energies into something, and you're bound to see some pretty steady progress.
I miss teaching -- the classroom part, the good days. I do not miss grading at all. I thought it would be hard to write without talking about and teaching about writing, but it wasn't. I thought it would be hard to write without a deadline -- September and the start of classes -- on the other end, but it wasn't. I thought it would be hard to write at home by myself inside my head all day instead of interacting with students and colleagues and a whole out loud world out there, but it wasn't. I worked so long and so hard and so formatively at teaching I thought giving it up would be much harder and stranger than in fact it's been. It feels like it's been much, much longer than a year.