@patagona thanks for the detailed report.
This looks like we need to decrease the input current limit to our charger IC before we start the transition from 5V to 20V. We will investigate a fix for the next bios release.
I remember in the PD spec, we need to drop the current to a very low value during voltage ramp for EPR transitions, I need to see if this is also the case for SPR voltage ranges as well.