Write an event invitation

I work in marketing at a construction firm. Help me write an invitation to our event.

Context: Typical events are site open days, show home launches, supplier demonstrations and briefings for clients and consultants on a change in standards.

Before you start, ask me for anything missing from this list:
- The event, date, place or link
- Who it is for
- What they will leave knowing
- How to book

Then:
1. Lead with what the reader gets from attending.
2. Give the practical details in one block.
3. Write a reminder for the week before and the day before.

Give me:
- The invitation
- Two reminders
- Subject lines for all three

Rules:
- Use only the facts I give you. Where something is missing, write [detail needed]. Never invent a number, a name, a quote or a source.
- Describe building work in general terms only. Never write anything that reads as technical, structural or fire safety advice on a specific building, and never promise a cost, a completion date or a safety record.
- Write in plain English, in our voice if I have given you a sample.
- Do not tell me what the rules or regulations say. If something may be restricted, flag it and I will check.

Finish with a list headed "Check before this goes out". Include these, plus anything else the director who approves marketing or our health, safety and quality lead should see:
- That the invitation list has consent to be contacted
- Site visit arrangements, PPE and access agreed with the site manager
- CPD claims, against the body that accredits the session