Change in attitude/conduct is mainly because of the feedbacks he gets from Salman Khan on WKV.
I don't think he is the type to listen to anyone who he thinks are inferior to him in intellect, stature or younger than him. So him listening to Sana or Asim and changing his ways is unlikely.
He pays attention to what Salman says probably because he looks upto him just the way Asim looks upto him.
He is smart and takes all the hints that Salman gives unlike others who argue with Salman when he points out to them.
This weekend Salman didn't thrash him for his fight with Asim instead he took extra effort to praise Asim and appreciate him for saying all those things to Sid on his face that made him realise that he was in the wrong and that boy was right.He toned down his aggressive body language when Salman told him that it looks bad.
He does spend a lot of time with Sana mainly because she is the much needed diversion in that closed environment.Don't think she has any influence on him it looks like the other way.She seems to be under his influence.
When it comes to tasks he still plays an aggressive game and plays to win.
If he takes all the tips that Salman has been giving him and changes his ways permanently he will definitely come out as winner not only in the contest but also in life.