Despite what I have heard, I am not able to swipe up and down to rate a photo with speed review turned on. I am using an iPhone 7 plus 64gb. The only thing it lets me do is flag or reject.
I use the iPad but I think ti works the same. Hold your finger on a photo until a menu appears. Check Speed Rating or Speed Review Combined. When using combined you have to swipe on the right side to rate stars. left side will flagg.
Strange, last night the only option was enable speed review, with no combined option. I restarted and the same thing happened. Today I fired it up and it worked fine!