Why it's short, and what you get.
The trial is Unlimited — every checker, every integration, the full dashboard. It runs for 3 days by design: long enough to evaluate on real traffic, short enough that a competitor can't quietly map the whole product surface.
It's one trial per server: re-registering with a new email on the same machine won't reset the clock. Upgrade any time from the cabinet — your instance keeps running without reinstall.