What I feel is this tearing of letter signifies is the first sign of rebellion from Shaurya against his Badi maa and bade papa.
He definitely knows that Tej is the only one who can issue this letter and still he tore it away because he couldn't even think of Anokhi leaving SIAC and going away from him, moreover he most certainly is sure that she can't cheat.
For me, this is the point where the show is going to take a turn for Shaurya's character. He will start looking things from the perspective of what is right, rather than his family's perspective which is going to be a great thing I feel.
What do y'll think about it? Do let me know!
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