Recently I got a new job in the company where I worked. This involved a payrise and I had to sign a new contract. The company produced a contract (Contract A) which listed the number of hours as 40, and the pay as 20k/ year. No problem with that and I accepted the contract and dropped it off in person to the HR department. The company had signed the contract already, and my signature made it valid. I had a copy to keep which the company also signed.
Out of the blue, I received another contract (Contract B) in the post listing the numbers of hours as 38 and the pay as 23k. The com