After your trial is over and you are happy with how Alfred has automated all your Linkedin tasks, you will receive an email notification indicating that your trial has expired and that your campaigns are paused.
You will also see the following notification on the dashboard page.
To upgrade, simply click on your profile photo on the Alfred website and then click on Billing.
Once you are in the billing page, you will be able to insert your credit card details and get upgraded immediately as shown below.
Please note that you will likely need to unpause campaigns after upgrading so they continue running as expected. Upgrading doesn't automatically restart campaigns unfortunately.