Forward shading and TAA

I upgraded my project plugin from 5.5 to 5.6 which is based on Pixel Streaming and the Alialising is broken . The VR template project that I upgraded had TAA and forward shading was off . I made the necessary changes required to be built for 5.6 like using GraphBuilder and DGTexture . I would like to mention that I create the swapchain witht the format PF_R8G8B8A8 and the texture descriptions that I carried over from 5.5 . What I have observed is that when the stereo rendering kicks in as the head mounted devices move the alaising is lost and the rendering quality has dropped . However if I enable the Forward Shading , the MSAA is implied and the quality is as the earlier version .

What are the changes I need to do to keep supporting “Deferred Shading” with TAA ?