I've been at this school for coming up to 5 years, starting as an NQT. It's not been an easy experience as the headteacher for the first 4 years was a bully and regularly had staff in tears. As it was my first experience of teaching, I accepted a lot of it and thought it was "right". I've since found out this is not the case and have been slowly starting to unravel everything over this past year. The current headteacher has expressed concerns about my mental health, not truly understanding why I'm not "better" as she "isn't the previous headteacher". I've recently had someone say to me that I was conditioned for 4 years so it's no wonder I respond how I do in school. Anyway, I'd been considering resigning and was told by the headteacher back in March that I would be moving year groups into KS2 so I should take that in to consideration with my decision. I did not hand in my notice but was then told less than a week after the deadline that I would instead by moving to EYFS. It's not necessarily that I don't want to do it but I feel that she told me to make my decision based on one thing, changed her mind after the deadline and has offered no real explanation other than "it's best for the school". Had the deadline not passed, she would have already had my resignation letter as I feel it was a very underhand move and feel it would be good to have a clean break from a school that holds so many bad memories. I contacted my union for advice and they said she's not in breach of contract but I could look at a grievance route as she told me one thing to stay and then changed it. I'd much rather not go down legal proceedings and rather ask for early release to go at the end of the year. How would I go about this? What would I say in the letter? Is it likely to be accepted?