Yes. You do not have the absolute right to choose when you take your holiday, and your employer can tell you when to take your leave.
However, unless your contract specifies otherwise, your employer must give you at least 2 days' notice for every day they want you to take. So if your employer is telling you that you must take 4 days' holiday, they need to tell you this at least 8 days' in advance.
Also, your employer can refuse your request for a specific holiday date (provided it has a legitimate reason).
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