I was a bit nervous about this as the Canonical site says that the latest version of Ubuntu may not run on the Thinkpad P14s:
Pre-installed in some regions with a custom Ubuntu image that takes advantage of the system’s hardware features and may include additional software. Standard images of Ubuntu may not work well, or at all.
Indeed, on booting up the laptop is indeed has a custom kernel 5.14.0-1047-oem and Ubuntu 20.04 (Focal Fossal). But I was determined to upgrade to 22.04. After upgrading the hard drive to 2TB PCIe 4.0 I noticed that in this model (21J5) there are NO slots for memory expansion. So you're stuck with the soldered 32GB it comes with. However, the installation went smoothly. I chose "Install 3rd party software for graphics and wifi". After installation I rebooted and tested wifi, sleep, suspend, closing the lid and connecting to a dock with two screens, keyboard and mouse. Also tested the function keys. All was fine. So I'd recommend this model for those of us who want a Linux laptop and don't want to pay the Microsoft tax.