I've tried upgrading using the webinterface and the downloaded extracted zip-file again today (just like i did early), end this time it did work. I'm now at version 1.5.1 The app and automatic update...

@TP-Link i've sent the system logs with the app. And a screenshot from the webinterface, showing all versions:

Model: Deco M9 Plus Hardware Version: V2 Firmware Version: 1.4.3 @crizthebard I Have the same problem. The app and web interface show 1.4.3 Build 20200921 Rel. 42500 as current version. Checking for...