The free trial lasts 24 hours from activation, is limited to one per customer and cannot be extended. A paid plan lasts for the duration purchased and allows the number of simultaneous streams selected at checkout.
A paid order normally receives its own credentials, which may differ from the trial login. The service is the same, but content availability can change and is not guaranteed by a past trial lineup.
To renew an existing paid subscription, use the same email and choose Extend Subscription. This normally keeps the existing line and credentials and adds time.