This discount will be over at Jun 12, 2017 10:00am US Pacific.
To celebrate the housing system revamp that went live yesterday we are offering a 20% discount on all subscriptions bought on steam this week!
(You will see the discount once you have placed the subscription in your steam-cart.)
If you want to know more about the housing revamp check out this post:
http://steamcommunity.com/games/287920/announcements/detail/1253537422577108228