Apple’s new $29 out-of-warranty battery replacement fee is now effective immediately, the company’s website says. Apple had previously said customers would have to wait until next month.

Apple announced it was lowering its out-of-warranty battery replacement cost after recent backlash from customers after the company admitted it slows down older iPhone models. Apple said it slows down devices because lithium-ion batteries lose capacity over time. To avoid devices from unexpectedly shutting down, Apple slows down older models to they can conduct certain tasks.

Apple’s battery replacement fee was previously $79, but Apple lowered the price this week to deal with the criticism. The current $29 price applies to customers who have an iPhone 6 or later. The lower price is “now available worldwide through December 2018,” Apple says.

The immediate availability of the lower price means customers can pop into an Apple Store and have their battery replaced for less than $30. Users can also ship their devices to Apple to get their iPhone’s battery replaced. However, customers who send their iPhone to Apple will have to be without a smartphone for a few days.

While Apple has sped up the launch of the lower price, battery availability could be limited, the company told Axios.

“We expected to need more time to be ready, but we are happy to offer our customers the lower pricing right away,” Apple told Axios. “Initial supplies of some replacement batteries may be limited.”

The company announced the new price in its apology letter to customers about the slow down of older iPhones.

“We know that some of you feel Apple has let you down. We apologize.” Apple said in the letter. The company added that there has “been a lot of misunderstanding” about the issue.

"First and foremost, we have never — and would never — do anything to intentionally shorten the life of any Apple product, or degrade the user experience to drive customer upgrades," Apple said in the letter. "Our goal has always been to create products that our customers love, and making iPhones last as long as possible is an important part of that.”

Customers who are under an AppleCare plan or warranty won’t have to pay the fee. iPhone 6, iPhone 6s, iPhone SE and iPhone 7 users should first check if they are still covered by their warranty, AppleCare Plan or consumer law. If they are, Apple will replace the battery for free.