I don't know if this is actually valid to do, but I've had success with 
destaining my GMS stains by de-Zenkerizing (put in Lugol's iodine for 10 min 
or more, then in sodium thiosulfate for 10 min, rinse in running water 10 min 
or more). This might work with Steiner, but it's a much more demanding 
technique than GMS. Worth a try, though, I think