EDIT: They are unrestricted in their running, so expect them anywhere.
I rode the 17.05 down Werribee, which formed the 18.03 up, and Brendan03 (yes.... that Brendan! ) was at Werribee for.
We ran on time as far as Laverton Junction, we sat there for a minute as the 17.11 down (super express) was running late, it passed us there, and almost as soon as it cleared the junction we were moving again. We arrived into platform 1 at Laverton as the express was departing platform 2. This allowed us to stay (close to) on time while letting the late running express get sufficiently ahead of us as well. Most passengers leaving at Laverton were rather confused at the location of the platform. We crossed back to the correct track just before Aircraft. I must say, its very good to see the bi-di being used for small advantages like this. Two thumbs up to the signaller at Newport!
It formed the 18.49 down Broadmeadows after that, which I didn't ride.
Coley was on the train for the two previous runs it did, which were the 13.45 down Werribee and return, and the 15.34 down Sydenham and return.
Hansonator also spotted this set running a Broadmeadows earlier this morning.
While it is still reletively "uncommon"... lets post sightings here.... and stop once it becomes widespread.