Hello, my name is Ben and it is my pleasure to assist you with your question today. What are your specific queries about this? Please note I am mobile at present so may not be able to reply immediately but will do so ASAP
Apologies for the delay in responding for some reason the system had not notified me that you were waiting for my response and I have only just seen it by accident.
Your employer should adhere to the terms of your contract and if it says that you are working on a 5/7 rotas then you can expect them to honour that. There could be a clause in the contract which may say you would be asked to work such additional hours that your employer may need you to, so it is also important that you check for that. If such a clause exists then it is possible to be asked to work additional hours to meet the needs of the business but this should not be taken advantage of and the employer needs to act in a fair manner. In any event there would be an implied contractual term in every employment relationship which requires the employer to treat its employees with a degree of trust and confidence, which basically means that you need to be treated fairly and not taken advantage of. So if the employer asks you to do additional hours on an occasional basis only and such a clause exists, then they could do it and you would be expected to help out as required (subject to negotiating the days you would be working and being given adequate notice).
However, if no such clause exists then the employer cannot ask you to work these extra hours and they would be acting in breach of the contract you have with them. You would then be able to refuse to do the hours that are asked of you in addition of he contracted ones and if necessary you may also pursue this through the employer’s formal grievance procedure. The final option, but only if absolutely necessary, is to resign and claim constructive dismissal in the employment tribunal.
Hope this clarifies your position? If you could please let me know that would be great, thank you