Where did you get in my text that I work for Neptune?
The warning is that there are no tests remaining, no? Assuming that the OP was getting valid results, I dont see how air in the line would effect the calculated amount used

.
Also not sure where you got that I am dismissing a problem. I am just explaining the need to have an excess of reagent in the bottle- which is needed for several reasons. Priming the system, doing the calibration, etc.
The "problem" seems to be that there is excess reagent..
Do you work for Apex, MnFish? Or at least have any experience with the product at hand?
Didn't think so.
Dont give out false information- or did you forget to say "In my opinion" in your post
"Nothing should be left if the notification says its 'empty'. If its a warning - perhaps at 10%"