Outdoor 800m prediction

Are you doing those 200's and 300's at 400 pace? I do similar workouts just with a few more reps but they are at 800 pace. It all depends on how you felt doing them, but you should definitely be able to run sub 2:04 based on those.

A better predictor might be a couple 400's at 800 pace or a cut down like 600, 500, 400, 300, 200, 100 at 800 pace.

This is a very special workout called a "Race". You do a mile or two mile warmup, do drills and then do 1x800 wearing spikes on a track at 800m race pace. I usually don't follow with a mile cooldown because I'm hoovering the concessions stand. If you can run somewhere around 2:10, then sub 2:04 would be an attainable goal for outdoor as of right now.