I deleted the 3 thread devices I had in smartthings in hopes of merging with apple homekit. The join option is still grayed out. They really need an override on this.
Not sure what else to do. I removed them all. I waited an hour. I rebooted the hub. No luck.
Resetting the hub is not an option. I have way too many legacy z wave devices. It would take me days to set everything up again. (84 iot devices of mixed type)
I have not heard of anyone successfully merging a ST thread network with an existing thread network apart from when you add a ST hub to a hub group.
When I setup my apple homepod mini it did ask which existing thread network to join.
Tagging @Automated_House
I unified both my V3 and V4 hubs into my Apple Home thread network this past weekend. Both are not in a hub group.
Did your ST hubs have any thread devices connected?
the v3 (58.10) had one thread device for testing (Eve plug). the v4 (58.12) was new with no devices. It took the v4 about 5 minutes to fully complete and about 10 minutes for the v3. I have since removed the plug and put it back on the Apple Home as my primary controller.