DH is on 0.78 PT. His (newly appointed) headteacher emailed today saying that actually he is on 0.6 as this is what his timetable represents, and so she will need to cut his salary by multiple thousands of pounds (approaching a quarter of the current amount he earns) OR he will need to start working an extra morning a week. She sent him a contract that he doesn't recognise that pre-dates his current one that he holds (both unsigned due to lax previous Head) that specifies that he is on 0.6. His newer contract (unsigned) does not specify 0.78 but he has copies of letters from previous years including this last year specifying his salary and the 0.78. He's been on 0.78 for about 8 years we think, employed there under two previous Heads before this one was employed last September. Can she actually do this?