From the release notes for rekordbox 5.5.0:
"Added plug-and-play function that activates rekordbox dj (PERFORMANCE mode) software when you connect selected controllers (DDJ-800, DDJ-400 and DDJ-1000) without requiring a license key. To use rekordbox dj on your computer without connecting the DDJ-800, DDJ-400 or DDJ-1000, you’ll still need to activate the rekordbox dj license (a license key card is included in the box)."
As I see it, you can use your DDJ-1000 in the future without restrictions on any laptop with rekordbox – without a license.
But rekordbox must be activated with a license on a laptop if none of the three mentioned DDJ controllers is connected.