The article mentions that it would take 30 days of being at 0 charge before the battery break.
From the article: "Of course you can drive a Model S to 0 percent charge, but even in that circumstance, if you plug it in within 30 days, the battery will recover normally."
So just discharging the battery to 0% gives you a month to charge it back; if you're at ~50% and leave it in the airport, it will be fine for over a year. (12 months to discharge to 0% and more time after that while it's still recoverable.)
From the article: "Of course you can drive a Model S to 0 percent charge, but even in that circumstance, if you plug it in within 30 days, the battery will recover normally."
So just discharging the battery to 0% gives you a month to charge it back; if you're at ~50% and leave it in the airport, it will be fine for over a year. (12 months to discharge to 0% and more time after that while it's still recoverable.)