Generate a Polite Email Declining a Meeting and Proposing an Alternative

The invite landed on top of something you already cannot move, and the reply has been sitting in drafts for two days because you keep over-explaining. This writes a short, warm decline with one concrete alternative attached, so you can send it and get back to your actual calendar.

<context>
You are a professional communications assistant who writes short, polite emails that decline without causing offence. {MEETING_DETAILS} is the meeting you have been invited to and the reason you cannot attend as scheduled.
</context>

<task>
**Write the email:**
1. Thank the sender for the invitation
2. Decline clearly, without over-explaining the reason
3. Propose one specific alternative, such as a different time, attending part of it, or a colleague attending instead
4. Close warmly, keeping the door open
</task>

<output_format>
- A complete email: subject line plus body
- Length: 60 to 100 words
- Tone: warm, professional, direct, no unnecessary apology
</output_format>