So many tools...
You don't need a reason to not be able to log on. What if your free company just wanted to take a break or play another game together? Someone shouldn't have to keep subscribed every month to make sure their large in-game investment doesn't get taken from them for no good reason. It's just plain stupid.
A FC full of close-knit bros might go play another game for a few months and then come back to the game when a new patch hits. Sure, SE loses out on those subscriptions for a couple of months, but that's all they lose. If they come back to having something they put effort into being taken away from them though, they might say 'screw it' and play a game that isn't run by dbags instead. Who is more likely to unsubscribe for good? The guys who had their house (Which are a pain in the ass to acquire) taken away, or some dude who thinks "Lol lyke no one is using that plot for over a month, that upsets me for some reason derp-a-herp"? They're not doing ANYONE any favors here. It's just an idiotic proposed system.
Now I know some of you have very flimsy grasps of logic and think that this is good because it frees up space or whatever for other people to get houses. But guess what? SE could just add more wards. Why can't they? They can afford more servers and developers who can actually set-up and run things better. So why not? The options were never choose between either take people's stuff away after a short amount of time of inactivity or no houses for everyone else. False dilemma, look it up.
Not saying they shouldn't free up current wards at all, ever. 90 days would make a lot more sense considering that's around the time between major content updates, and is just a more reasonable amount of time. They could also add a way for people that know they're going to take a break to sell back their plots and building permits so they can get compensated, at least partially, so they're not getting completely boned. "But people will still complain that it is too short..." That's not an argument. Why not make it 8 hours then? People will complain either way, after all. Some time frames are still more reasonable then others. 90 days coincides with major content updates, at least. About a month coincides with...hmmm, subscription charges? Does SE really want to make it seem like this is just a ploy to keep people subscribed indefinitely with threat of punishment? That makes them look incompetent, because if they were good at making a game people would just stay subscribed because the game is full of enjoyable content and they wouldn't need to resort to such pathetic tactics like this.