Spawning minicopters get more seats after server restart

I spawn minis on roads via command minicopter.population.
These always come in vanilla shape.
Now I added your plugin to give players a reason to buy minis still to have more seats.
But after a server restart all minis that have been spawned and claimed and parked in player's bases have 4 seats also.
Can you prevent this?

Btw. weirdly the extra seats stay at claimed minis after having unloaded the plugin and restarted the server.