Also on the topic of anchoring... if I reset the Guardian (I'm experimenting with an oversized Roomscale Guardian vs turning Guardian off) with either a long-press of the Oculus button or by going into the Guardian Settings, the layout goes out of alignment by the same vector as the Guardian when anchored to the new Guardian.
If the device goes to sleep (say, I take it off to answer the door then come back a few minutes later) not only is the layout skewed by angle but often lifts up a couple of feet, giving me the same perspective in VR as my 4-year-old in RL. This will definitely happen if the guardian is Stationary when it goes to sleep but opens at roomscale guardian when it wakes.
One possible solution is to return to alignment (with transparent walls and AR on) after any interruption of the app or guardian.