I dont hv sources but this is what i believe..
Sana and Paras were offered this show almost a month and half ago when articles started floating and were made to sign the contract too ..Thats why articles started floating in media bec they signed contract and so channel knew they cannot back out now ..
Only thing is both sana and paras mayb kept in dark that its swayambar kind of show ..Mayb they were told its like splitsvilla type and they could not say no especially sana as she feels indebted to colors ..
Sid was unhappy bec she signed such show ..even though they dint hv clear idea of show but deep down they knew its dating type show and so sid was upset when she signed it ..Its that gautam/kartik week only ..
Sana signed it fr 2 reasons ..One she feels indebted to colors..second that time she was not sure of her as well as sid ka feelings ..After that week only both realised they hv serious feelings fr each other but by that time she had already signed contract and could not back out of it bec she can get into legal mess then ..
Eventually sid decided to support her and they might hv spoken about hiding their relationship till this show is over ..
This is my common logic of whole scenario..
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