Definitely Pre-FS1 in my view, but it is not GTA. It looks a little to bodged together (no offense Swamp) to be military issue, but rather a pirate or merc ship, which is a cross between an assault fighter and a light bomber. I've heard speculation/discussion that early encounters between Vasudans and Terrans was actually through merchants and traders rather than military or diplomatic expeditions. These craft would seem to date to that era of a less regulated trade environment when the GTA had yet to expand and provide protection for civil traffic from these Pirates. Either the pirates or the Mercs that fight them would use these craft... though I'm leaning towards the pirates, since Mercs are mostly escort and wouldn't need bomber-type craft.