Can ALVR ask to render and encode a larger area of FoV?

I have been studying on this project for a while. And I am wondering if ALVR can ask steam VR and the Encoder to render and encode a larger area of the scene (larger than the usual FoV size). I am thinking about this because this can somehow avoid black edge area because when moving the headset, the client can see the area around the FoV area even if the new scene has not been transmitted. This may be helpful especially when the network latency is high and head movement is quick.

I find that the "width" and "height" parameter in ALVR refers to the resolution instead of the size of video. In my understanding, implementation fo this solution may be related with change in both the driver, the encoder/decoder and the OpenGL part. As a beginner in programming I am wondering if this solution can be implemented in ALVR and how. Any advice or idea is appreciated! ：)