I monitored the traffic between my BS6500 and BL7000. Seems like the Beolink queries the time only once, when the button lights and the "standby" text timeout on the charger. From there on, it seems to keep the time by itself with no traffic between them. I followed that for maybe 15 minutes, I'm sure they will sync periodically some time later if nothing else happens.
Also, the BL7000 and the MCP seem somehow aware of each other, as the other one always goes "off" immediately when the Beomaster sends something to the other. But all the Beolink 7000's have the same protocol address, so they will surely get confused if there is more than one on the same "bus" (either direct infrared in the vicinity of the Beomaster, or on the MCL in the linkrooms).