The notice is effective as soon as it is issued. The employer may not withdraw the notice except by agreement. The effective date of termination should be stated and the notice of termination of employment should be not less than what is stated in the contract of employment.
If no notice period is specified in the contract, then the law sets minimum periods of notice which your employer must give, according to the length of time you have worked for your employer. For example, if you have worked for your employer for more than a month but less than 2 years, the law says that your employer must give you at least a week’s notice.
Also, if you disagree with the reason for your dismissal, or are concerned about the way that the dismissal was handled, you should speak with your union or seek your own legal advice. You may well be able to challenge your employer in an employment tribunal (any claim will need to be brought promptly - almost always within three months of the dismissal).
