I have a permanent 3,3V on VCC_BATT pin (SODIMM 40) to keep the time.
Basically, my issue is that when I remove all power rails from the module, except VCC_BATT, my main rail is still powered between 3,0V and and 3,2V (it powers other modules on our main board).
Cutting the supply track to VCC_BATT pin fixes my issue, but this not acceptable, it just shows the issue happends inside the SoM.
I have verified, as you recommend it, that all my SNVS pins with any attached load are set to 0 before entering the “RTC Only” state, but it doesn’t change anything.
I also read your errata file : https://docs.toradex.com/105707-colibri-imx6ull-errata.pdf
How does the switch between SNVS rail ans main rail that you added in version 1.1 works ? Can this switch keep powering main rail with SNVS one ? Or any other module (such as wifi) that still powered by SNVS rail and sends back this power in main rail ?