That's not it. They will keep the assets closed and under license. There will be no free version of the full game.
Not sure why we should encourage using open source as a vehicle to market and get free work building your fundamentals. Just to reap the profits yourself later.
The multiplayer game (the thing available now) will remain free including all the updates and improvements to it. What will be behind a one-off-payment will be the campaign. We've had a few bad actors spread word that the entire thing is going to be behind paywall, microtransactions, pay-to-win etc but none of that is true.