Questions about Homematic IP Access Point

I have two - the second one extends the maximum number of devices.

Yes, this access point can be used as a wireless amplifier for the CCU3. It can be registered as a device on the CCU3 control centre and then takes over the function of increasing the range for the CCU3, provided that both are connected to the same network. A maximum of two access points can be used per installation, with the second increasing the range and taking over the function of the first in the event of interference.

Yes, the AccessPoint is required as a gateway (HM radio to IP). The actuators communicate on an 868.3 MHz radio, not directly in the W-LAN.