Around 9:25 would be quite good for her and does not seem impossible. 9:14 would be sensational and I am pretty sure she has no chance to break 9:20 this time.
And there is still quite a way to go between 9:19 and 9:14.
Gesa Krause ran 9:32 at 19, 9:23 at a 20, 9:19 (in the 2015 worlds final) at a little older (just 23) than Ostrander is now and it took her another two years to get to 9:15 and 9:11 in 2017.
Emma didn’t break 9:20 until she was 24 (Shanghai 2014)