Delivery of your emails depends on your AWS SES sending limits. Let's say your 'Sending Quota' is 100,000 emails per day and 'Send Rate' is 14 emails/second. In theory it would take approximately 60 minutes to send 50,000 emails.
In reality it would take a bit longer to deliver emails. Our real-world sending stats indicate average delivery times about 2 times the theoretical value.
Once an email is delivered it would trigger various delivery notifications (sent, delivered, bounced, opened, clicked, complaint, etc.). While 'sent' and 'delivered' stats come in quickly, the rest can take their own sweet time because they are dependent on the recipient email server and end user actions.