When I was researching what it was like to work in China, a common complaint I read was that school administrators were forever throwing curve balls. Sometimes you don't even know when the school holidays are until they are upon you. Or someone phones you and tells you that you're expected to be at a meeting or teach a class you knew nothing about. Or you are expected to volunteer your time at some student activity. Or you feel disrespected because you are obviously out of the loop on a lot of things.
The advice that I read and took to heart was, try not to get irritated by any of this. Just go with the flow. Say "no" to demands that you think are unreasonable but otherwise, hey, would it kill you to do some extra-curricular stuff like English Corner? In fact, being friendly and open may well lead to more opportunities. Being stand-offish and prickly will only increase the ESL teacher's feelings of isolation.
And I've learned the hard way (and I use the term the "hard way" because that's the common phrase, but in fact it was devastating) that all the dedication and devotion in the world doesn't mean squat when people in a position of power have their own agendas. The only thing I could take away from that was, I know I'll never put myself in that position ever again. Of course I'll fulfill my obligations and take pride in doing a good job, but I'll never let a job become my entire identity. So here, if I make what I think is a great suggestion and it goes nowhere, or plans and schedules change from day to day, I don't let it get under my skin. But again, it might feel different when you're a young person and this is one of your first adult jobs. And I think I've been treated well by my employers and not every ESL teacher in China can say that.
There are some stories on the internet about ESL teachers who packed up and left in the middle of the night because their working and/or living conditions were horrible. I can't speak to that and wouldn't presume to advise anyone. But -- no matter what happens, will you be proud of what you did and said? Will you be able to say you acted with integrity? When things turn to crap, this is no small consolation. I'd only say that my little issues here have been effectively handled with honey, not vinegar.