Tesla has extended a deadline for potential customers to lock in unlimited use of its fast charging network known as Superchargers by another two weeks.
The electric car company tweeted Sunday that customers have until January 15 to order a Model S or Model X and still receive unlimited Supercharging, a network of 769 fast-charging stations located near interstates throughout the continental U.S., Europe, China, and Japan. The previous deadline was Jan. 1.
Tesla (TSLA) also posted an update to a November blog that had announced the changes to Supercharging. The update says “due to high demand, customers can still place an order for a Model S or X until January 15th, 2017 and take delivery by April 15, 2017 to receive free unlimited Supercharging.”
Get Data Sheet, Fortune’s technology newsletter.
All Tesla cars will continue to come standard with the hardware required for Supercharging. A Supercharger provides up to 170 miles of range in about 30 minutes.
In November, Tesla announced customers who buy cars after January 1, 2017 will have 400 kilowatt hours, or about 1,000 miles, of free charging every year. Once an owner surpasses that amount, a small fee will be charged. Tesla says the amount will cost less than the price of filling up a comparable gas car without providing specific figures.
Last month, Tesla introduced an idling fee of 40 cents per minute that will be imposed on drivers who leave their cars in a Supercharger space for more than five minutes after they’ve finished charging.