It's an odd story.

1. Mid-2018, Panasonic issues a warning about risk of battery overheating.

2. Near end of 2018, I start getting pop-up notice to update my bios. I ignore it.

3. Laptop still running normally - approx 20 sec from power on to PW screen

4. I start getting full screen popup notices from Panasonic saying I must upgrade my bios and battery charging firmware.

5. Around the same time as #2 or#4, my startup to PW goes to 2:20. It wasn't obvious whether it was the same period or somewhat before or after, so I didn't realize there could be a connection.

6. The full screen popup from Panasonic only appeared after boot, password entry, Windows desktop, and all startup programs were running. Thus, it did not occur to me that this could be part of the pre-PW boot delay.

7. The first boot trace I posted here, earlier in this thread, did not seem to show any delay related to Panasonic. The worst delay you found was from my custom modified MS keyboard driver. But that had not changed at any time.

8. Yesterday, I finally gave in to Panasonic and downloaded the bios and battery charger firmware updates, and ran the install program.

9. The popup disappeared and the laptop is back to full speed booting.  That is, I am back to square #1. I am still using the old Intel video driver, which I was not able to update. Still using the old IRST driver, which I have not tried to update. And still using the old, modified MS French-Canadian, which I will not change if I can avoid it.

What this means to me is that Panasonic did something that slowed bootup tremendously. It was either intentional or just bad programming of the update warning program.