Today moved for the third time too the new Conbee III stick.
The previous attempts where unsuccessful.
The system is now running for some hours and did bot lose any devices.
Only the Aqara multi sensors had to be reconnected again.
Some issues with deConz and the interface are still there.
Some switches which are working fine, but are not present in the interface.
They where present for two years but the last few month they are not present anymore.
For the moment the move to the Conbee III stick is successful.
Might be worth to check the firmware version too, the latest version 0x264f0900 beta changelog has a few fixes which are important for newer Zigbee 3.0 devices.
It can be upgraded as described in Wiki: Update deCONZ manually
All, are the latest version, firmware and deConz. (stable)
The present errors are deConz, the last few versions.
There has been improvements, for the first time I am able to use the Conbee III stick.
The previous attempt I had to go back, all was to instable.
Devices disconnecting etc. (disaster)
Tne first steps are made, that we can use the new stick.