Grandstream Networks UCM6510 User Manual page 259

Delay Before Callback
Destination
Firmware Version 1.0.10.39
Configure the number of seconds to be delayed before calling back the
user.
Configure the destination which the callback will direct the caller to. Two
destinations are available:

IVR

DISA
The caller can then enter the desired number to dial out via UCM6510
trunk.
UCM6510 IP PBX User Manual Page 258 of 339