I could be really off on this but all my references (including Ali'd'Italia #12) show that plane (252 Squadriglia BT, 104 Gruppo, 46 Stormo Aerosilurante / Sardinia, 1940-1941) with a camo with Gray (not Sand / Giallo Mimetico) overpainted with Olive Green mottling not yellow. Verde Olivo Scuro 2 over Grigio Azzuro Chiaro 1
If it WAS painted in olive over yellow/sand I would LOVE to see a picture of it.
Here's the profiles from Wings Palette -with a pic of the actual plane on the bottom: