The first thing to check is your contract and terms and conditions of employment to see what these say about your hours of work. Some employers offer flexible working arrangements but if your hours are, for example, 9 to 5 and do not vary in practice, any change to this arrangement will require your employer's consent. This will in turn depend on the nature of your employer's business and the need to have staff available to cover specific hours.
However, you can certainly request a temporary adjustment to your hours, and it may be possible to arrange something with your colleagues to ensure that the employers needs are still covered while you take it in turns to come in and leave earlier or later to avoid rush hour. If you have a workplace union rep it would be worth speaking to them to see if they could raise the possibility of introducing flexible working with your employer on behalf of you and your colleagues.
It is worth noting that working parents with children aged under 17 (18 if disabled), and employees who are also carers, have the right to request a change to their working hours, once they have worked for their employer for a year. However, the main purpose of this legal entitlement is to accommodate care arrangements and any change agreed to by the employer is usually a permanent change to your terms and conditions.
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