AppleTV 4K Slow Updates

Updated AppleTV 4K to TVOS 26.4. Despite automatic update being enabled, the AppleTV never automatically updates. After clicking update, progress bar says Downloading 2 minutes. Five minutes later, the progress bar moved to 50% and the text reads 4 minutes. At 75% of the way, the time bounces around quickly from 2 minutes to 3 hours to 26 minutes to 1 minute. At 80%, the text under the progress bar changes to Preparing... Download time took about 5 minutes.

The update slowly progresses stuck on Preparing... for the next 10-15 minutes while the progress bar crawls to 95% at which point it jumps to the install screen, that progress bar moving quickly, finally the the unit restarts. Done.

What is the device doing while is is "Preparing...?" Does the verify really take twice or three times as long as the download? Or is the device busily uploading viewing data to Apple, Netflix, Max, YoutubeTV, and Prime - which are the only platorms on the AppleTV?

Unit is on a wire, ISP 1gig to the prem, ISP router into an Apple Airport Extreme configured as a bridge, so out to the AppleTV just under a gig.

Speed tests from any computer or device within the LAN, wired or wireless, is always around 950m/s.

AppleTV is shut off every evening and started up each day.

AppleTV never has a problem streaming from any of the aforementioned platforms.