[RKCRLR]

I just got a 2019 Shield TV Pro. 
I can't get AI upscaling to work on ATSC 1080i and 480i 59.94 FPS content (which my understanding is Kodi de-interlaces to progressive).  I get a message "AI-Enhanced not active: unsupported content".  
However, AI upscaling works on native 720p content.  
I don't have anything in the whitelist and I've set the resolution to 3848x2160p & Refresh rate to 59.54 Hz.  
My TV is receiving at 3848x2160p resolution.  
I'm on Shield TV Experience 8.2.2.  

My understanding is the Shield TV Pro should do AI Enhanced upscaling on 1080p 60FPS content when running software version 8.2, is that correct?  If so, are there some specific settings I need to do in Kodi to make it work?

Read the green field on this page:

AI UPSCALING

Also,
in KODI settings,
if you want to upscale any content, played with it,
DO NOT use the resolution whitelist feature.
Leave the resolution fields blank.

I'm assuming you're referring to this from the page:

AI Upscaling is not available for the following types of content:
Video resolution is less than 480p
Video frame rate higher than 30Hz
Video content color space is RGB
AI Enhanced upscaling will fallback to “Enhanced” in these cases

That page appears to be out of date.  The 8.2 update increases the AI-Enhanced framerate to 60 FPS:

https://www.nvidia.com/en-us/shield/software-update/

However, I'm aware that it won't work on an interlaced source which isn't mentioned on those pages.  But I'm also aware that Kodi on Android automatically de-interlaces the interlaced source material.  In fact, I've been told there is no way to disable the de-interlacing in Android Kodi.  And the de-interlacing option is greyed out.  

But this brings up another nuance.  My TV takes a few seconds to switch resolutions .  If the TV Guide is in one resolution but the source material is in a different resolution then it takes a few seconds before I can see the video after starting it and another few seconds after I stop the video to see the Guide.  So if I make the Guide the same resolution as the source material I normally play (1080i most of the time) then I can eliminate the delay.  So if I whitelist the 1080p material (1080 material upscaled by my TV is noticeably better than when upscaled by the Shield Enhanced Mode) and set the Resolution to 1080p I can eliminate the delay.  But, for some reason, the 720p material (that isn't whitelisted) gets played at 1080p even though I have my player settings to adjust refresh rate on start/stop.  So now it is getting an upscale to 1080 once by the Shield and then again to 4K by my TV.  I can manually override it to play at 4k.  

I can eliminate the delay on stop if I change the Resolution to 4K and change the player to adjust the refresh rate on start but if I do that the Resolution will get stuck at 1080 for some reason and again upscales the 720p material to 1080p.  

My preference would be to have the Shield upscale all 720 and 1080 FPS material to 4K in AI-Enhanced mode if possible.