[Thinkpad Tablet General] kbhasi:
I can't properly write this post as I'm tired, but I may edit it later tomorrow

What I can mention now is that on my side, I received the update too, and was taken by surprise, but it seems that Lenovo's Android updater is very aggressive, and seemingly more aggressive than the Kindle device updater.

The former actually tried to force the update on my rooted YT3 Pro, however, I saw a notification indicating that the update failed (I was too alarmed to take a screenshot of that), and I could tell it restarted, as transitions were disabled again (I manually enable them after every restart, especially when it runs out of power), and it was showing over 1 hour of uptime (it restarted at around 10:30 AM (and went back to Android system at 10:32 AM), judging by screenshot file dates) after charging it overnight while on.

The build number for the update appears to be slightly different on my end, and I originally thought it was due to a regional thing, but I was probably thinking of Samsung Galaxy. Instead, the build number is most likely different due to me having the YT3-X90F variant, which is the only 64 GB storage variant if I recall correctly.

YT3-X90F_USFLS200322 1706140050 WW17_BP ROW_TO_YT3-X90F_USFLS200375_2003021924_WW17 BP ROW

Note the differences in build dates. 2017-06-14 00:50 jumping straight to 2020-03-02 19:24. Also 322 jumping to 375, so I have to wonder what was going on at Lenovo's Android division with that, but it probably just a lot of failed builds.

I've previously complained over at the Lenovo Community forums (my username there is "MustardOrMayo"), and I did get a "kudos" (called a "thanks" over here) for that in the lead-up to this, but didn't too much about that because the user "DnSage" who did that didn't reply

and

I don't think they're a Lenovo employee either as the only one I've seen there has "_Lenovo" in their username.

From what I can see with the most recent posts (last 6 posts on page 2, first 2 posts on page 3), their update was forced too, it also affected some Yoga Tab 2 models, it seems that it may be a bootloader update, and I think that may be what it is, as it's a 14 MB update, rather than significantly larger full Android system updates.

I've a feeling that Lenovo is planning to just push security updates only, and not update the Android system (to at least Android 7.1 which the Android variants of the original Yoga Book already received, but not the Yoga Tab 3 Pro whose 64 GB variant runs on the same hardware platform!!) because of Google's requirements for GMS certification that they have in order to reduce the chances of devices being released with outdated Android releases (they have cut-off dates for GMS certification for device certification and certification for Android releases on said devices, if I recall correctly), which I think Lenovo was notorious for in the past, so it's probably just going to be stuck on Android 6, but if they're anything like Likebook (who coincidentally still uses Android 6, but mainly because they use the older Rockchip RK3368) or Boox, they'll at least try fixing their buggy UX, however, those two brands I mentioned can't get GMS licencing and certification as of yet (Android doesn't officially support e-paper AFAIK), but Lenovo may have a problem as they do obviously produce devices for the consumer market.

I'll attach screenshots here, mainly for those who don't have one and are curious.

I've a feeling similar things may be going on or have been tried by Lenovo's Motorola team, who appear to have their own Android security bulletin website (there doesn't seem to be one for Lenovo Android products), and Lenovo is probably having their Android team learn from the Motorola team, and/or are taking in new engineers to help. I mean, on Android, 14 MB sounds like it's just a bootloader and/or recovery update.

I'm just hoping that this bootloader can still be unlocked and I can run the temporary TWRP session in order to root it.