Phal. schilleriana and Phal. stuartiana both have mottled leaves. You've done a great job growing that plant. Ohh -- Phal. schilleriana also has a mild fragrance.
I consider this to be one of those store finds, it was in a 2 inch tiny pot packed with Sphag.moss and I knew they would probably kill it. It had a 3inch spike with 2 small flowers almost faded away.
I got it home and it did nothing for close to 4 months (all summer) Sept hit and it went nuts!
It now sits in a 5in pot packed with roots. I really love this one, its done so well, so far