Just for clarification, I'm assuming you're referring to external callers calling your system correct?
What type of phone lines are attached to the UC560? Are they Analog, ISDN, PRI, or VoIP (SIP)?
With Analog lines, Caller ID information is not transferred until after the first ring. This is the reason why almost every system with analog lines are configured to answer after 2 rings.
If you don't have Caller ID information (or don't use it), you can set the system to answer after 1 ring.
You can change this under CCA by going to Telephony > Ports and Trunks > PSTN Trunks > (Selecting an FXO Port) > Edit Settings > Timers > Number of Rings for Caller ID Alerting
ISDN, PRI and VoIP trunks don't have this requirement. In fact, they can answer the call immediately (even before the calling phone has a chance to ring).