I need a response to a customer complaint about a delayed shipment. The response should be formal and polite, and it should include an apology and an explanation for the delay. Additionally, the response should contain at least 3 placeholders represented by square brackets, such as [name], [order number], and [expected delivery date]. The response must also include the keyword "sincerely" and should be at least 100 words long. Please ensure the response is professional and empathetic.
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