If you use ZHA for Zigbee on #HomeAssistant, and have been considering upgrading from the Sky Connect or ZBT-1 to the ZBT-2 - Rest assured the migration process is one of the easiest things I've ever done with a computer.
Plug in ZBT-2. In devices, click Add on the disovered ZBT-2. Pick Migrate. Do what it says. It'll tell you when it's time to unplug your ZBT-1 or Sky Connect. My Zigbee network restabalized in the short amount of time I was distracted by an itch on my foot.