The R15 was used and Oppo utilized the notch so well. The R17 just came in, but this time I pretty think it might shrink it down. We had seen photos by TENAA , but the one at the front was too dark to comprehend or to make out any detail from it. These two images from Weibo show an Essential -style notch, though with a slightly different design.
It does seem, the Oppo R17 would only include a selfie camera, and an ear piece in the notch. Well if you can look at the separate glass panel in the first photo, it gives a more concrete look and it isn't just clear where the proximity sensor and ambient light sensor go in all this setup.
This also just doesn't answer where the finger print sensor(reader) was placed - it isn't at the back, check the TENAA photos. And by the way, the Oppo F9 pro, would also have the same design( notch- design). Of course, the R series model will be a higher end offering and it could have as much as a whooping 10GB of RAM( that's soo crazy!).