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

I have a similar but slightly different issue that has been an ongoing issue for my iPhone 15 Pro Max, even during trial testing. 

My RBE871 and connected 870's are on 10.5.16.325719

There was noted improvement of random disconnections (even upstairs).

My iPhone 15 Pro Max is configured for Wi-Fi6e AUTO.

IPv6 IS disabled.

Network settings were recently reset entirely on the iPhone to remove any potential hidden or undesirable settings.

My RBE871 hands my phone off to my basement RBE870 when I'm in the basement (approximately 60 feet away diagonally). While this seems to be a recurring issue, it's not isolated to ONLY the basement.

My RBE871 is approximately 90 feet to the RBE 980 and 140 feet to an upstairs RBE870 that is in my pantry that is roughly 50 feet diagonally and horizontally (meaning pantry is on the main floor with the 871 router).

Intermittently, whether with or without an active call, my Wi-Fi status icon will drop 1 bar to 2 of 3 bars.

Shortly thereafter a full disconnection will occur and I'll failover to a single bar of LTE (tough issue with my provider and unable to resolve).

IF I am on an active Wi-Fi call via ATT using voice and this behavior occurs, I must return to the upper level of my home to re-establish Wi-Fi connectivity and eventually Wi-Fi calling via ATT.

While reviewing settings to compare against recommended from apple (Recommended settings for Wi-Fi routers and access points - Apple Support), I noted repeat DHCP requests occurring during my outage window from the web-based log. I've filtered the MAC a little, but it's definitely the one for my Wi-Fi interface and the IP my device has been using and is well within the outage window.

[DHCP IP: 10.168.168.129] to MAC address ea:28:f9:xx:xx:xx, Tuesday, July 29, 2025 11:06:39
[DHCP IP: 10.168.168.129] to MAC address ea:28:f9:xx:xx:xx, Tuesday, July 29, 2025 11:06:24
[DHCP IP: 10.168.168.129] to MAC address ea:28:f9:xx:xx:xx, Tuesday, July 29, 2025 11:06:21
[DHCP IP: 10.168.168.129] to MAC address ea:28:f9:xx:xx:xx, Tuesday, July 29, 2025 11:06:20

I'm able to provide logs (including of when the incident occurred today) to you if desired, but I can't help but wonder if the device is having DHCP trouble as possibly indicated below.  In the interim, I'll test the OP's suggested work-around to see if this aids in my ongoing issue.

Edit:  I also noticed a large amount of queries from my phone throughout the prior evening, and a healthy amount of queries from my AppleTV (4k).