@ShieldSean 

Here is a new response we recieved from our Engineering team

The DNS would influence both local-only and schedule issue as schedule need to work based on correct time and device neet to talk to NTP server to get the correct time.
if DNS has some issue, there might be something blocking the device from talking to the NTP server, also the DNS issue would block the device from connecting to our cloud server and that's the reason why RD team said that would be a DNS issue.

I am not sure why the new firmware would trigger the devices to go to local only if it's possible, could you please ask those users to send their device MAC and TP-Link ID as well as the host router's model number so we can check more details to locate the issue,

So we would suggest trying to change the DNS and if that does not work.  email your device and MAC addresses to ussupportteam@tp-link.com and we will send it to them to investigate further. 

@Carl Pretty much as I expected, changing the IPv4 and IPv6 DNS servers in my Eero did nothing. One KP200 is normal, the other KP200 is Local Only, but they're both connected to the Eero hosted wifi network. I'll email the device info screenshots over to support and we'll see what we can dig up.

I don't see any issues with DNS or NTP OTA and I continue to run IPv4 on the SSID the strips connect to. What I am seeing is if there is a power failure (whole home) when the power returns the Kasa strip is failing to reassociate to the access points, as they are still booting. It then does not recover from that state, e.g. does not appear to periodically retry to associate. I suspect the same may be true if I was to reboot my access points, but have not tried it yet.

Things to consider in my setup - I am running commercial, not consumer, wireless. Multiple APs all centrally managed with the same config and roaming enabled (I work for a very large networking company), however when the power cicles, none will be available for the duration of their boot time, which is likely longer than the Kasa strips.

With the network running normally, if I unplug the stips from the wall and then re-plug them, once they boot, the Local Only goes away until the next power glitch. One of the strips does appear more resiliant than the other, but they are running the same firmware, associate with the same SSID, etc. 

@Scanners 

Update - it is not related to power. No power incidents, but the strips randomly drop off. One of the strips is online... except 1 outlet that shows as Local Only. 

Really sucks - none of my automations are working either scheduled directly on the strip, or through integration with SmartThings or Google Home. 

@Scanners that solved my problem, I power cycled the outlet from the breaker, and when it came back up it stopped reporting as local only. It's a bit discouraging that I have to unplug a hardwired outlet to make that happen.

@Carl maybe the software team can look into this, if the outlet loses power and then turns on before the network does it needs to check occasionally to see if it can get off local only. Or there needs to be a way to reboot the outlet without powering it and everything near it off from the breakers.

Moral of this story is, "Did you try turning it off and back on again?"

@Maryj i managed to fix the issue by creating a guest SSID on my wireless router and managed to connect all plugs! 

@Randopando 

Interesting.  What's different on your guest network than you primary?  I may consider this.  Is it just an internet only guest network so it bypasses all your internal network?  How long have the devices stayed on that network and remained connected?

I ask because each time I factory reset my plugs they stay connected for about a week then several of them flop back to local only....

@Carl 

Just thinking outside of the box.  My router uses both IP4 and IP6 addresses (one each) from my ISP on the public side of my router.  However, internally, I've shut off IPV6 becasue of one device I have internally (an older OpenVPN server) has issues when running on a network where both IPV4 and IPV6 are available.  Eventually I plan to switch over to a new device for the OpenVPN server for my external clients accessing internal network resources, I just haven't gotten around to it.

That said, I've left the public side of my Router running both IPV4 and IPV6.  This includes a primary DNS of my ISP in IPV4 and the secondary using IPV6.  Could this be causing issues for the plugs?  I say this only becuase, my plugs seem to randomly chose to go local only about once a week, but only a few do this.  I reset them to factory defaults and they come right back up.....however, they don't seem to be the same plugs each time.  I've done all the suggestions here so far, including reserving the addresses for each one in my DHCP server.

To be fair, I've not yet tried the resent suggestion if using a guest newtwork for the devices, because if this my ISPs Auto DNS settings are causing the issue, then the guest network wouldn't help.

Also, one of my H300 strips randomly, shows one or two plugs as local only while the rest are fine.....Seems to me as though there is a software glitch somewhere.  Perhaps if these devices could ping the router and interent once every couple hours once they go into Local Only mode this would resolve?

Lastly, my router is set to reboot twice a week on a schedule in the o-dark-early hours....I'm wondering if that could be causing some of this since it happens randomly to plugs and doesn't seem to be consistently on the same plugs?

Thanks for any input....

@Maryj 

This Locals only thing sucks.  I've plugged and unplugged, reset to factory for both  plugs and Alexa.  They will work a few minutes, then Plugs will turn to Local Only.  I am getting my return labels ready.

My  Bad Reviews will be all over the web soon.