Hi,
The asus rt-68u in my office has Model: RT-68U and HW version: A2 on the back, and, on the front, confusingly, AC1900 Dual Band.
It's running the official firmware : 3.0.0.4.386_51668-gc12f3e8 and master in a mesh configuration with another identical router/firmware and
a DSL-AC68U running...