Make the request, in writing
Ask in writing for advance notice of changes as a reasonable adjustment: tell your manager or HR that unplanned changes disadvantage you and request a set notice period plus time to process. No diagnosis is needed. Name the specific thing you need rather than a general complaint, for example: “Please give me at least two working days’ notice of changes to my rota, tasks or meetings, and time to plan for them.” An email is ideal because it creates a dated record. Acas lists having early warning of changes and extra time to take them in as a recognised adjustment for neurodivergent staff, and offers a free request letter template you can adapt Acas. You do not have to use the word “disability” or share any diagnosis to start the conversation.
Explain the disadvantage, then get it recorded
Spell out the effect in plain terms: last-minute changes leave you unable to prepare and perform as well as you otherwise would. That sentence matters because it names the legal trigger. The law calls your employer’s habit of changing things without notice a provision, criterion or practice, and once that practice puts a disabled worker at a substantial disadvantage, the employer has a duty to take reasonable steps to remove it Equality Act 2010, s.20. You are not asking for a favour; you are asking them to meet a duty that the law already places on them GOV.UK. Then ask for the agreed notice period to be written down, in an adjustments passport or a short written agreement, so it survives a change of manager and you are not renegotiating it every few months.
If the request is ignored or refused
If your manager does not respond, or refuses without a good reason, ask for the decision and the reason in writing. The next step is the employer’s formal grievance procedure. If that does not resolve it, you can contact Acas for early conciliation, the free step before any employment tribunal claim. A failure to make a reasonable adjustment is itself a form of disability discrimination and is difficult to defend where no alternative was offered s.21. Advance notice of change is usually a low-cost, low-effort adjustment, which makes an outright refusal harder still to justify. For the wider picture of what you can ask for, see what reasonable adjustments are under the Equality Act.
Where the law comes from
Related
This page is general information, not clinical or legal advice.