we implemented three cisco spark roomkit plus and one cisco spark roomkit. when we tried for failover test it failed. for example, if all spark roomkit registered to cucm publisher we will stop the cucm publisher service. then roomkit devices that are registered will get unregistered but never failover to subscriber. its the same case if we tried to register with cucm subscriber and then do he same thing. it will end the the same.
we tried with devices latest firmware. it gives the same result.
even if we started Call manager services back. it will not register back.
its been somany weeks now. cisco tac also couldnt help yet in this situation