https://wccftech.com/a15-bionic-orders-for-iphone-13-increased/

As demand for the iPhone 13 picks up, so do the chip orders, which in this case is the A15 Bionic. Unfortunately, as Apple reportedly asks its partner TSMC to increase wafer production, it has scaled down chip requirements for the previous-generation iPhone models, and there can be various reasons why this happened.

With the new iPhone 13 series, Apple also sells various models it launched previously, with iPhone 11 and the 2020 iPhone SE being the oldest. However, according to DigiTimes, MacRumors states that Apple is experiencing shipment delays for all iPhone 13 models, with customers having to wait between three to four weeks in the U.S., U.K., and Canada. Unfortunately, older handsets are not fairing well either, with the iPhone 11, which is still a popular model thanks to its impressive price-to-performance ratio, facing up to a five-week delay.