I think the reason the '292 Jack (and '392 Stockman version) were discontinued is due to the amount of overlap with other Case patterns in a similar size range. I think the '75 large stockman (essentially a larger version) and '47 stockman (same serpentine frame, but rounded bolsters) took over the Stockman range, and the '49 Copperhead and '54 Trapper designs covered the larger Jack range.
Case seems to have made a decision a few years back to focus only on certain patterns and let others die off, or go into their "Vault" of temporary discontinuation. I guess when they were cutting patterns from the lineup, something had to go, and the '92 (and '99 and '31 and '35 jacks) were some of the casualties. But they keep adding new ones, mostly from their relationship with Tony Bose, so I guess it's all part of the knife business.
If I were going to actually carry a Case 2-blade jack in that size range with a pen secondary, I'd probably opt for the Copperhead due to the rounded bolsters and sunken (more like covered) joint, just to save wear and tear on the pockets. In practice, when I want to carry a larger Case knife, it usually ends up being a regular Trapper.
Here are a couple of pics of some of mine, taken a while back, along with some of their Mini Copperhead kin:
Close-up of a blue one:
