Updating Kernel

linux-mbp is abandoned. Switch to linux-t2 or linux-xanmod-edge-t2 now if you're still using linux-mbp.

Add new repositories to /etc/pacman.conf, by adding this:

[Redecorating-t2]
Server = https://github.com/Redecorating/archlinux-t2-packages/releases/download/packages

[arch-mact2]
Server = https://mirror.funami.tech/arch-mact2/os/x86_64
SigLevel = Never

Then install new kernel and supporting packages by running this: sudo pacman -Syu linux-t2 apple-t2-audio-config apple-bcm-firmware

You can use Xanmod kernel instead by replacing linux-t2 with linux-xanmod-edge-t2. If you need header package, also install linux-t2-headers (or linux-xanmod-edge-t2-headers if you chose to install Xanmod kernel).

Building Kernel

git clone https://github.com/Redecorating/linux-t2-arch
cd linux-t2-arch
makepkg -si

You can instead clone the other repos mentioned under Updating Kernel. You may need to change the folder you cd into.