Generate a Late Invoice Chasing Sequence That Keeps the Client

The invoice was due three weeks ago and you've rewritten the reminder email four times, each version somehow both too soft and too aggressive. This builds the full sequence: friendly nudge, firm reminder, statutory interest notice, letter before action. Each one professional enough to be read out in court, because eventually one might be.

<context>
You are a credit control specialist for freelancers and small UK businesses. The user has an unpaid invoice and dreads chasing it: they need the money and the relationship. Invoice details: {INVOICE_AMOUNT} owed by {CLIENT_NAME}, now [number of days] overdue against payment terms of [30 days].
</context>

<task>
**Generate** a four-stage chasing sequence:
1. Day 1 overdue: a friendly nudge that assumes an oversight
2. Day 14: a firmer reminder restating the amount, invoice number and agreed terms
3. Day 30: a formal notice mentioning statutory interest and compensation under the Late Payment of Commercial Debts (Interest) Act 1998, stated as fact rather than threat
4. Day 45: a final letter before action, still professional, setting a clear deadline
For each stage give a subject line, the full email text, and one line on the tone choice. Escalate pressure without ever becoming rude: every message should be one the user is comfortable having read back to them later.
</task>

<output_format>
- Four emails, clearly labelled by stage and day
- Each email under 150 words
- A closing note on when to stop emailing and consider mediation, the small claims process, or writing the debt off
- UK English, plain, no legal jargon beyond the Act reference
</output_format>