We actually use the ID on the apps too. Since the apps can connect to the bond through MQTT (cloud), mDNS properties wouldn’t do any good there.
We are using this regex:
BRIDGE -> "^(Z|[A-C])\w*\$"
SBB_CEILING_FAN -> "^K\w*\$"
If in the future we have other kinds of SBBs, they will start with another letter