Update details-confirmation.md

Updated to more prominently emphasize critical information for speakers and relegate confirmation of details to lower down the email.

app/md/email-templates/details-confirmation.md

@@ -2,7 +2,14 @@ Hello {name},
 
 Congratulations! You are now confirmed to present about {topic} at the SeattleJS meetup on {date}. We're excited to have you join us!
 
-Before we publish the event details, we'd like to confirm your information. Here's the details from your submission - is there anything you'd like to change or are you happy with it as is?
+Here's what you need to know:
+
+1. You will be presenting on {date} at {location}
+2. As a presenter, we ask that you **arrive by 5PM** to complete a tech check before doors open at 5:30PM
+
+---
+
+Before we publish the event details, let's confirm your information. Here are the details from your submission.
 
 - **Name**: {name}
 - **Pronouns**: {pronouns}
@@ -12,7 +19,7 @@ Before we publish the event details, we'd like to confirm your information. Here
 - **Presentation Description**: {description}
 - **Topics**: {topics list}
 
-Let us know if that all looks good or any changes you'd like changed. Afterwards we will get you added to the meetup agenda!
+Let us know if that all looks good or if you'd like to make any changes. After you've confirmed the details, we will get them added to the meetup agenda!
 
 Best regards,