As Hurricane Irma was bearing down on Florida, Tesla Inc. sent a free software update extending the battery capacity for some of its vehicles, giving those owners extra range to flee the looming storm.

The update temporarily unlocked the full battery potential for 75-kilowatt-hour Model S sedans and Model X SUVs, adding another 30 to 40 miles to their range. The upgrade was first reported Saturday by the electric-car blog Electrek.

Starting in 2016, Tesla offered cheaper versions of the Model S and Model X with limited battery capacity. While they have a 75-kWh battery, software on those versions limits customers to using about 80% of available power, with a range of 200 to 230 miles per charge. Normally, unlocking the extra capacity costs about $3,000.

A Tesla spokesperson on Sunday confirmed the upgrade.

The change was apparently made after a Tesla owner in Florida reached out to the company and asked for a temporary upgrade to make it out of the evacuation zone. The upgrade for those Florida customers will remain in place until Sept. 16.

According to the blog Tesla Motors Club, the company sent a note to the owners who were upgraded, saying: “Due to these exceptional circumstances, and to help you better prepare to evacuate and get to safety, your vehicle has been adjusted at no cost to you to temporarily access the additional battery capacity until September 16th. You will notice the badging on the instrument cluster will read 75 during this period. We hope that this allows you to travel to your next destination with confidence and ease.”

Read:‘Worst-case scenario’ as Hurricane Irma makes landfall in Florida

About 6.5 million Florida residents were under mandatory evacuation orders over the weekend as Irma slammed into the state. A number of Florida Tesla owners posted on social media that the company’s Supercharger stations worked well and didn’t have the long lines that gas stations did.

Tesla TSLA, +4.42% shares are up 60% year to date, compared with the S&P 500’s SPX, -1.11% 10% gain.