It is no secret that all major US carriers may start throttling your unlimited data after it reaches a certain amount - Verizon and AT&T start at 22GB, Sprint at 23GB, and T-Mobile has a 28GB cap. Well, the latter cap just changed as T-Mobile recently increased it to 30GB. Instead of specifically announcing the change, the third largest wireless carrier in the country simply updated its "About" page to notify users about the new cap. Now that Verizon has brought back Unlimited Data, all four major carriers in the U.S. offer the said feature that's so popular among gamers and people who like to stream movies and music.
It's worth noting that the aforementioned limit only denotes the point at which T-Mobile may start throttling your data, but that won't necessarily happen. This limit just allows the carrier to cut down on your speed if they are experiencing heavy network traffic. While they want to honor those with unlimited data plans, the carrier's primary concern is managing their network speed so that all of their subscribers can enjoy the speeds they were promised when they joined the network. During periods when network traffic is light, the carrier could allow full speeds to the unlimited data user even if they have surpassed their designated data amount. Carriers generally want to make their users happy, especially when it comes to data speeds and the amount of data they're able to use, so T-Mobile will presumably stick to the practices outlined above.
Now that Verizon and AT&T have entered the world of unlimited data, raising the data throttling cap to 30GB may prove to be a wise move on T-Mobile's part in the long term seeing how it allows them to stay on top of what their significantly larger competitors are offering. It remains to be seen whether Sprint will follow suit now that T-Mobile has seemingly reacted to the new offerings from their competitors, but whatever happens, the increased competition on the market is usually always good news for consumers and there's no reason to believe that won't be the case this time.