My neighbor, who is a district 3 patrol officer says that it will be quite a while before they start using it. Its due to funding. The actually have the consoles and everything, they just do not have the funding to staff the district 3 console for quite some time. The radios were programmed with the dist 3 stuff in the beginning to keep from having to reprogram everything when dist 3 turned on.
Just to let you know how long it will be, station 14 which was built in 2002 and continues to sit empty is higher on the priority list than turning on dist 3. So it might be quite a while.
I would still monitor dist 3 channels as they are used for special events, stake outs and other activities occasionally