Apple exacerbated matters by allowing anyone to get a $29 replacement, regardless of the wear-level of their battery. For those that were even the slightest bit worried about performance degradation, they now have a quick and simple way to get a new battery.
Unfortunately for iPhone 6 Plus owners, this increased demand means that you will have to wait longer to receive a replacement. According to internal Apple documents obtained by MacRumors, Apple will not be able to replace the battery in your iPhone 6 Plus until late March or early April. So, if throttled performance is nagging you, you're going to have to put up with it for a few more months.
If you have an iPhone 6 or iPhone 6s Plus, the wait time is a more reasonable two weeks. And if you own an iPhone SE, iPhone 6s, iPhone 7 or iPhone 7 Plus, you should expect to be able to get your battery replaced "without extended delays".
Apple's iPhone throttling debacle sparked the ire of customer across the globe, and has even invited the prying eyes of regulators in France and South Korea. The company is also facing dozens of class-action lawsuits relating to the matter.