I don't own any modules yet, and it doesn't appear to be available... However, based on the statement below, I would think it should be:   
" 
      Starting today and lasting until 1 October 2018, play DCS: F/A-18C  Hornet, DCS: Persian Gulf Map, and the Su-33 for DCS World for free! The  Hornet and Su-33 include all the missions and campaigns as the  purchased versions, and they can be played in both single player and  multiplayer modes. Enjoy!  
       If you do not already own one of these modules, we hope you will take  advantage of this great opportunity and try out a new DCS World module  and consider a purchase.  
       For install any of those modules please see into Module Manager in the game."