Its been a long slog for Apple, they have been working on this since 2018, and they had to keep extending its supply agreements with Qualcomm...

"Inside Apple’s Spectacular Failure to Build a Key Part for Its New iPhones"

>The 2018 marching orders from Apple Chief Executive Tim Cook to design and build a modem chip—a part that connects iPhones to wireless carriers—led to the hiring of thousands of engineers. The goal was to sever Apple’s grudging dependence on Qualcomm, a longtime chip supplier that dominates the modem market. The obstacles to finishing the chip were largely of Apple’s own making, according to former company engineers and executives familiar with the project. Apple had planned to have its modem chip ready to use in the new iPhone models. But tests late last year found the chip was too slow and prone to overheating. Its circuit board was so big it would take up half an iPhone, making it unusable.

https://kanebridgenews.com/inside-apples-spectacular-failure... [2023]