The license for SQLite Expert Professional is perpetual. A perpetual license allows you to use the licensed software indefinitely. For the first year, the perpetual license also entitles you to download all updates to the software and to receive technical support.
If you choose the subscription option, after the one year period ends you will be billed automatically for the next year Updates and Support period, for 50% of the license price.
You can choose to remain with the last version downloaded by canceling the renewal of the Updates and Support plan before the next rebilling is due.