I still think Conte is only using 3-5-2 as an alternative to 4-3-3, rather than anything he would view as a first choice system.
He's only used 3-5-2 when a key player has been missing - generally Vucinic or Marchisio - or when he's using a lot of backup players in the Coppa.
There's no suggestion that when all options are available to Conte he won't play 4-3-3