Oooh. I do like a Titanium KHS and do own a few... From a casual glance your frame looks like a TiLite with the wrong decals but is different in a few ways, rear dropouts and all my bikes have a hole through the brace between the rear triange near the BB and on the one below the canti brace. Your cable holders on the top tube look identical to those on my TiLites and my Obed FS.. As does the Canti brake holder behind the seatpost. Your frame has the cut in the seatpost at the rear though and mine are on the front.. My Obed FS has it on the rear like yours.. Both my cable holders for the front mech on the seatpost on my TiLites and Obed look just like yours.
My KHS Ti frames have serial numbers and other things on the BB. Eg: ahfm51 950/011
What is on the underside of your BB?
So it clearly looks like it was built by Litespeed but has a few differences to my TiLites.. A nice problem to have regardless
Found this which is also another Montana Team in Titanium from a few years ago that looks just like yours.... https://www.pinkbike.com/buysell/2636166/ This has the same dropouts as yours. Thanks. I've just found another frame I need to buy. If you ever want to sell and yours is a 17" then please let me know!!!