>So then, if the planned depth is 2920 meters, how far down into the Roper Group we'll end up?

The BCGA should be in the Bessie Creek Sandstone.

"Finally, the Moroak and Bessie Creek sandstones offer a Basin Centered Gas Accumulation (BCGA) play at the center of the basin. It is an unconventional resource play characterized by a lack of a gas/water contact. Petrophysical analyses of several wells previously drilled in the basin demonstrate the presence of a BCGA in the basin."

"The most likely estimates of recoverable gas in the Moroak and Bessie Creek Sandstones are calculated to be 11.2 and 17.5 trillion cubic feet (Tcf) respectively. These estimates are based on a well spacing of 160 acres and 10% recovery from a calculated most likely, in-place gas resource of 119 Tcf in the Moroak Sandstone and 174.9 Tcf in the Bessie Creek Sandstone. "

In September 2007, Sweetpea drilled and cased one well the Shenandoah #1 to a total depth of 1,555 meters (4,740 feet) in the area covered by Exploration Permit (“EP”) 98 in the Beetaloo Basin. The test was a twin (50 meter distance) from the Balmain #1 well and was designed to test the Bessie Creek Formation at a depth of approximately 3,000 meters.

Then again, they might just keep on drilling until they run out of money :)