I have a TP-Link Deco XE75 Pro AXE5400 Tri-Band Wi-Fi 6E "Whole Home Mesh System (3-Pack)" that I setup and have been running since late October 2023. The system is fast when deivices are connected. However, known devices all take a long time to reconnect to the network after powering on. Sometimes up to a minute or greater. This is occurring on Smart TVs, Laptops, Gaming Devices, iPhones, and tablets.

The environment is as follows:

• 3 story home with main Deco on the middle level and connected Decos upstairs and down
• 940Mbps Century Link Fiber
• Operation Mode is Wi-Fi Router - Main Deco is connected directly to the network
• Internet Connection is IPv4 (IPv6 is disabled)
• 6GHz Network is reserved for Dedicated Backhaul only
• Guest Network is off
• SIP ALG, UPNP and IPTV/VLAN are Enabled
• I am not using a VPN Server
• Firmware is current per the Deco App at 1.2.7
• The system has about 35 known devices, and 15-20 are typically connected (thought not necessarily in use) at any one time

I have attempted the following, and nothing has made any difference whatsoever:

• Fast Roaming is disabled
• Beamforming is disabled
• QoS is disabled
• Set Device Connection preferences for stationary devices to the closest Deco
• Set Device Connection preferences to always connect to 5Ghz or 2.4Ghz
• Disabled Mesh Technology for stationary devices
• Run Network Optimization daily
• Restart the network daily 

Initially I did have the system setup via AP mode where the network ran through my old Century Link modem first. I experienced the same connection delay issue I am having now. When I switched over to Wi-Fi Router mode with a direct connection I did a full reset of the Deco system so that it could be setup fresh. Probably irrelevant to the issue at hand, but after switching from AP mode to Router I no longer receive Connection Alert push notifications from the Deco app, even thgough the notification setting is turned on (although they do appear in messages).  

I'm at my witts end with this one and the return policy just expired. Any help would be greatly appreciated. 

Thank you!