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nRF52840 -> VDD vs. VDDH and GPIO reference voltage configuration

Hi,

As mentioned in the Ch. 5 "nRF52840_DK_PB_v1.0.pdf" Section 5.3 in "high power mode the external supply should be connected to just the "VDDH" pins and "VDD" pins not connected to any supply." 

A) But, I referred the Nordic's Forum link - https://devzone.nordicsemi.com/f/nordic-q-a/30851/nrf52840-high-voltage-mode---external-circuitry-supply that says that in high power mode the recommended caps. to be connected to VDD pins..

Any specific reason for connecting the caps on VDD pins in high power mode, other than just noise reduction/ avoid ground coupling ?

B) In high power mode, if GPIO reference follows the VDD (as in the forum link - https://devzone.nordicsemi.com/f/nordic-q-a/30851/nrf52840-high-voltage-mode---external-circuitry-supply) then with respect to the configuration value on "REGOUT0" register the voltage level should follow VDDH and not VDD as mentioned in the Ch. 4 -> Section 4.5.1.8 "nRF52840_DK_PB_v1.0.pdf" product spec. document.

C) In high power mode, why to connect the external supply to VDD  (as in the above forum link)..?? In contrast, as mentioned in the product spec. it says not to connect any supply on "VDD" pin when "high power mode"is required ?

D) how and through which pins the voltage can be supplied to external circuits by configuring the internal LDO or DC/DC regulator when nRF is in "High power mode"?

Please provide clarity/ guidance on this as there is difference in the conditions mentioned in the above forum link and the product spec. document for VDD, VDDH and GPIO reference voltage levels. 

Thanks.

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