On the depthcharge path the built-in drivers probe at ~0.7 s while the root is still the embedded stub, so iwlwifi and the SOF DSP fail their firmware loads and give up before the real initramfs is unpacked. The Lenovo 500e booted with no wifi and no sound card, so no TTS greeting and no connection. After unpacking, the stub now points firmware_class.path at the unpacked tree, unbinds and rebinds the Intel/Realtek wifi and sof-audio PCI drivers, and waits up to 8 s for a wl* interface and a sound card before switch_root.