Interesting to note that while the seller is very specific about it being an Omega Cal 911 movement, the balance bridge in the pictures, is marked as a Cal 865, which is a Chronostop movement if I recall correctly, further reinforcing the notion that a watchmaker had a barrel of parts and tried to make something out of his leftovers.
Again, I'm no expert, but do know what a Flightmaster looks like and that it has a 910 or 911 calibre. I will give the credit if it indeed really runs and functions as a Flightmaster should.