An eCommerce company are running a promotional campaign and expect a large volume of user sign-ups on a web page that collects user information and preferences. The website runs on Amazon EC2 instances and uses an Amazon RDS for PostgreSQL DB instance. The volume of traffic is expected to be high and may be unpredictable with several spikes in activity. The traffic will result in a large number of database writes. A solutions architect needs to build a solution that does not change the underlying data model and ensures that submissions are not dropped before they are committed to the database. Which solution meets these requirements?