Device flipping to celllular/disconnecting when on WiFi? Read this for possible solution!

I just tested using an iPhone 15 Pro Max on iOS 18.6 (22G86) and not only did the issue return when set to "automatic", it failed to re-connect to the Wi-Fi on its own for about a minute, which is more than the usual 10-15 seconds I previously observed.

After this encounter, I tested and re-tested moving around the house.  Disabling Wi-Fi for a minute, turning back on and testing around the house again.  I used airplane mode and disabled Wi-Fi as well, waited a minute and re-tested.  I even went into the Wi-Fi settings menu and could see a spinning circle on the SSID for my house.

Test methodology was:

• 1 round of walking around the hosue and stopping in various rooms and placing the phone down. 
• 1 round of using SpeedTest.Net's iOS App to run their video test which helps generate traffic across the connection while moving to various rooms and also placing the phone down.  During testing, I would note that the signal strength indicator for Wi-Fi would drop 1 bar, but would return within a few seconds.  I never dropped the Wi-Fi the entire time according to the status icons.

Approximately 30-45 minutes later, I was playing a mobile game and received a Wi-Fi connection alert.  I checked and sure enough I had showed as disconnected.  I ran down to my office and checked a "ping -t" I had running against my phone and confirmed "Destination host unreachable" as well as various request time outs during the incident.

Ping statistics for 10.168.168.129:
    Packets: Sent = 2833, Received = 2802, Lost = 31 (1% loss),
Approximate round trip times in milli-seconds:
    Minimum = 3ms, Maximum = 1221ms, Average = 44ms

Reply from 10.168.168.129: bytes=32 time=14ms TTL=64
Request timed out.
Reply from 10.168.168.129: bytes=32 time=126ms TTL=64
Reply from 10.168.168.129: bytes=32 time=118ms TTL=64
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Reply from 10.168.168.128: Destination host unreachable.
Reply from 10.168.168.128: Destination host unreachable.
Reply from 10.168.168.128: Destination host unreachable.
Reply from 10.168.168.128: Destination host unreachable.
Reply from 10.168.168.128: Destination host unreachable.
Reply from 10.168.168.128: Destination host unreachable.
Reply from 10.168.168.128: Destination host unreachable.
Reply from 10.168.168.128: Destination host unreachable.
Reply from 10.168.168.128: Destination host unreachable.
Request timed out.
Reply from 10.168.168.129: bytes=32 time=20ms TTL=64
Reply from 10.168.168.129: bytes=32 time=82ms TTL=64
Reply from 10.168.168.129: bytes=32 time=7ms TTL=64
Reply from 10.168.168.129: bytes=32 time=108ms TTL=64