IOS-XE upgrade 16.3.6 to 16.6.7 performed microcode upgrade for non-PoE 3850

[Feds]

Hi everyone,

IOS-XE 16.6.x Release Notes for 3850 model https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3850/software/release/16-6/release_notes/ol-16-6-3850.html 
state: 
"During an IOS image upgrade or downgrade on a PoE or UPoE switch, the microcode is updated to reflect applicable feature enhancements and bug fixes."
"The microcode update occurs only during an image upgrade or downgrade on PoE or UPoE switches. It does not occur during switch reloads or on non-PoE switches."

Yesterday I upgraded a WS-C3850-24XS-E (which is not PoE nor UPoE afaik) from 16.3.6 to 16.6.7, and the microcode was indeed upgraded.

Did anyone have the same experience?

Cheers

Fed

[Leo Laohoo]

Look at the two versions: The switch is upgrading from 16.3.X to 16.6.X.
A microcode upgrade is bound to happen because they are different "train.
Microde upgrade is not necessary when upgrading to the same "train", example 16.6.5 to 16.6.7.

[Feds]

Thank you Leo (it's always a privilege receiving your answer!), problem is RN don't state that, so they are misleading when it comes to calculate the outage, or if you do it remotely with no console access and switch doens't come back in 10 mins.

At least for bootloader, RNs are generic enough "For subsequent IOS XE 16.x.x releases, if there is a new bootloader in that release, it may be automatically upgraded based on the hardware version of the switch when you boot up your switch with the new image for the first time".
But one thing is staying vague, another is stating "done only for PoE or UPoE switches".

Thanks
Fed

[Leo Laohoo]

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@Feds wrote:

or if you do it remotely with no console access and switch doens't come back in 10 mins.

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 Always prepare for a 30 minute outage, micro-code upgrade or not.  

[Feds]

Sure, good suggestion. Thank you.