To what extent can an employer use rationalisation to change shifts and achieve redundancies

Due to my company's quality department being reorganised all quality control engineers positions are redundant. We had the option to apply for new positions or take redundancy. The old quality department was/is made up of three different cells for the thee main products the company manufactures. We are all expected to be multifunctional within our roles. I was employed to work the night shift as a quality control engineer. I had been in the position for 4 years and was served my redundancy notice in September 2007 to finish in July 2008. On March 18th went to a meeting where it was requested that I move onto day shift with effect from April 14. The position I will be moving into is that of a colleague that will be made redundant at the end of April. Q1; Can the company move me into a redundant position? Q2; I expected to work nights benefiting from my night shift premium until my redundancy date. I have only been offered 1 months premium for moving onto days. Q3; My contract has a variation in statement that states I have to be given 1 month's notice to change my shift pattern. Can my hours of work be changed whilst on a redundancy notice. As seen above in Q1 i have not been given the full 1 month's notice.