Yes, through the FCC, then there's a couple of immigration desks prior to the walkway to Domestic.

Last time I did it, three weeks ago, I took the bus to the FCC and instead of joining the winding queue, turned right at the top of the escalator, thru T1 immigration, out to landside, up the stairs, thru Domestic Security, and was in the lounge in 20 minutes. Fluke ? probably (T3 arrival gate was close in) but will definitely try that again next time.