Yes, that's true, for initial assignments and coordinatation with other Special Operations Division and select Detective Bureau assets.
But, once the initial assignment is received, A6, along with most other Emergency Service units will switch to the radio zone covering the incident's address to coordinate with precinct units also responding. In addition, once on scene, A6, again, like most ESSs, can switch to a Tac channel to coordinate on-scene operations. There's no point in tying up a repeated channel when all you're trying to do is talk from the front yard to the MOS covering the backyard.
My point? To give such a curt answer to the OPs question does a disservice to the OP. If the OP asked what channel is A6 dispatched on, then yes, SOD is fine. But A6 can communicate across a wide range of department (and non-department) channels.