Unfortunately I could not get there in time, work on saturday yesterday, and today they will close in about 1h. But I promise, I get there and tell you about it.
Actually, there is a video of the new 223 A10 rifle of Steyr, from Austria Arms. And they recorded the video inside the Steyr Mannlicher Shop here in Wr. Neustadt, and so in the back left side you can see A2 model, a green M9-A2 framed model. But I m sure they have the L green frame as well.
About the STM, the presenter from Austria Arms, when he introduces the STM, in the very first sentences he say "This is the Steyr AR-15, but deep inside its heart it is an AUG

". The then demonstrate the toolles barrel swap, that's in the AUG as well. And AR-unlike the STM upper and handguard is a single piece, and the gas system is also from the AUG.