I work alone in an office and my contracted hours are 11pm – 8am. I agreed to work from home over Christmas (8pm Christmas Eve until 8am Christmas morning and 5pm Christmas Day until 8am Boxing Day). Was told on the morning of Christmas Eve that there were some hitches that needed sorted and I would be contacted later in the day to discuss. Boss left voicemail in the afternoon asking me to call him, no reason given, I called back when I picked the message up at 1845. He then told me that I needed to work from the office instead of home. I explained I could not work a 12 hour shift in the office alone, at such short notice (90 minutes). I offered to work my normal hours. I was told I had to work the hours I agreed to or not work any. Can he do this given that my contracted hours are only 11pm – 8am and the extended hours were really just to help out because no-one else would work Christmas Night? Some more questions, Is there a minimum number of hours rest you should have between shifts (I would only have 9 hours) and Can I be expected to work 15 hours alone in an office with no guarantee of breaks due to the nature of the job?
Many thanks for your help.

Marie Mackay