Question XRUpdateEarlyUpdate taking way too much time

Hi!
I have some issues regarding the performance of my VR application.
I'm running my .apk on a Pico Neo 3 Pro, with Unity 2021.3.5f1 and URP 12.1.7.

When I run in editor, everything is fine. But when I run the app in-headset and profile it, I get a minimum time of at least 8 ms per frame spent on EarlyUpdate.XRUpdate - in a basically empty scene. These are not spikes - the time usage is pretty stable, staying between 15 and 20 ms. This really hinders the performance of the app when I enter a scene with more than 1 or 2 simple meshes.

The thing is that with a previous version of the same project, using Unity 2019.3.4 and URP 7.3.1, these performance issues are not present - with EarlyUpdate.XRUpdate taking as low as 2 ms on a relatively complex scene.

I'm using the same settings and same SDK (Pico SDK 2.11) on my headset for both the old and new versions of the project. My graphic settings are all tuned pretty low, and I am not using any complex shader.

I have seen some posts here regarding the performance of EarlyUpdate.XRUpdate, but I did not see any concrete explanation or solution regarding this specific case. I've also seen some posts regarding a performance degradation when going to a more recent version of URP, which prompts me to consider going back to something like URP 10 or even URP 7.

Before I go back to a previous version of URP, is there any way I could fix those issues ?

Thank you all!