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System resetting after removing USB cable

Hello!

We have a custom board connected to a battery and a USB cable

Our fw calls:

NRF_POWER->SYSTEMOFF = 1;
The board turns off.
And then we remove the USB cable, and the board turns back on again. We don't have any event handler set up.
I saw a similar question regarding that problem here:
https://devzone.nordicsemi.com/f/nordic-q-a/38659/usb-disconnect-causing-system-reset

But it is a very old question and the HW errata pointed out by the Nordic employee doesn't even apply to the HW revision we are using which is QIAAD0 (according to the packaging).
One workaround we found was to add a delay before it actually calls SYSTEMOFF, if the cable is removed before this delay is elapsed, the board doesn't turn back on again. So looks like whatever is making the board reset, gets enabled only after the SYSTEMOFF is called.

Is this behavior expected? Is there a way to disable it?
Thank you so much!
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