I am a teacher. I get paid for 1265 hours a year spread out over 12 months. My contract does also say 'you may be required on occasions to work additional hours'.
The problem, I have found in previous schools, is what is considered to be reasonable when it comes to working those additional hours. When I go back to school next week, I will spend usually between 2-3 hrs a day beyond my contracted hours to get planning, marking, admin done, plus whatever work I do during weekends/holidays. Usually, I don't mind as long as I have professional autonomy.
Unfortunately, I have worked in schools where working additional hours were considered 'reasonable' were in fact completely unreasonable. If you fail to keep up to to unrealistic policies (e.g. marking every piece of work every child did in each lesson - I work secondary and teach over 150 different kids every day), despite working ridiculous hours ticking off lots of useless crap that doesn't actually help children, they eventually start capability procedures. With no union representation, you can only jump ship.
I guess my point is that I don't mind the additional working hours in my contract, as long as they're not going make me burn out, that the tasks I spend time on actually helps the kids that I teach and I am not wasting precious unpaid time on tasks that only serve to tick a box.
Unfortunately, a lot of schools exploit this part of the contract. My contract says I am not entitled to be paid overtime.
Perhaps teachers, and other professionals, should just be paid for the hours they actually work to get the job done (including the work done in the holidays/weekends), rather than paid a salary. I doubt this would ever happen though. Probably would work out more expensive 😅