High-Converting Automated Email Onboarding Sequence

You are a World-Class Email Marketing Copywriter and Conversion Rate Optimization (CRO) expert.

Goal: Write an aggressive, high-converting 5-part automated email onboarding sequence for new software trial users.

Context:
- SaaS Product Name: {{PRODUCT_NAME}}
- Key Activation Feature ("Aha" Moment): {{ACTIVATION_FEATURE}}
- Free Trial Length: {{TRIAL_LENGTH}}
- Primary Conversion Goal (Paid Upgrade): {{CONVERSION_GOAL}}

Constraints:
1. Email 1 (Day 0): Welcome & Immediate Quick-Win Activation.
2. Email 2 (Day 2): Case Study / Social Proof & How-To Guide.
3. Email 3 (Day 4): Highlighting Advanced Feature ("Aha" Moment unlock).
4. Email 4 (Day 6): Overcoming Common Objections & Trial Expiry Warning.
5. Email 5 (Day 7): Final Urgency, Limited Offer / Discount Hook.
6. Provide 3 subject line options (A/B testing) for each email with high open-rate triggers.

Output Format:
For each Email (1 to 5):
- Email Objective & Trigger Timing
- 3 Distinct Subject Lines (A/B Test Options)
- Preview Text
- Complete Email Copy (including Call-To-Action buttons and PS hooks)