A: Your next step should be to contact your professional association and ask for assistance. It is for this sort of occasion that you pay your annual membership fee. You will need to build up a case by documenting the time and the additional responsibilities that you are taking and demonstrate that you have no slack as a result of, say, less need for cover or invigilation duties.
It could be that this is a rebalancing of your non-contact time if it is above the national required figure (10 per cent). However, if you are being singled out for different treatment from your colleagues, you will need to bring this to the attention of your association representative to ensure that there is no discrimination.
In the end, if you don't make any progress and still consider the responsibilities to be unacceptable, you have two options open to you: accept them or look for another job. The former might be worth doing if the responsibilities can help with your next promotion. The latter will require you to seek a reference from your headteacher at some point and a bad-tempered row over the extra responsibilities may not be the best way to start such a conversation. You can always explain in your letter of resignation why you are leaving. But even then it is often better to keep your reasons to yourself as you never know what is around the next corner.
John Howson is a recruitment analyst and visiting professor of education at Oxford Brookes University. To ask him a question, email him at email@example.com.