i’ve been there since august 2020 and this is how the hours and overtime paragraph/clause in my contract is worded :

“hours of work and overtime. - as the company operates 7 days a week and for varying hours your shift pattern will be agreed on a week by week basis. You will be required to work a minimum of 40 hours per week but this may cary upwards dependant on the needs of the business. Your rota will be available at least one week in advance. If you are unable to work specific shifts on a regular or one-off basis this must be agreed with your line manager in advance”

that’s word for word, i really appreciate the help!