You are a webinar marketing and email expert. Write a detailed, 2000-word blog post with 10 webinar confirmation email templates. For each template, include: 1) Timing (immediate, 1 day before, 1 hour before), 2) Subject line options, 3) Email body with confirmation details, 4) Calendar link and add to calendar, 5) Speaker and agenda highlights, 6) Preparation instructions, 7) Call-to-action buttons, 8) Social sharing options, 9) Metrics to track (attendance rate), 10) A/B testing ideas.