Hi,
I think that if the creatives were thinking of taking the story into that direction then Pia would have lost her memory just after her engagement to Jai. That way she would have assumed to be married to him by now and know that the child is his, but the fact that her memory goes back to the time before she found out about Jai's crush, kind of indicates that she will still presume to be inlove with Pushkar....and the creatives will try and rekindle Pia and Pushkar's romance.
Unless someone like Jigs tells her that the baby she is carrying is Jai Walia's and Pia just assumes that she married Jai. Then maybe Bani will say to Jai that they have to play along with it because the doctors have said that if the truth comes out then she could get a huge shock and die and lose the baby.
One thing for sure is that the creatives do not know where to take the 'whose the father' story with Jai, Pia and Pushkar. I think for a possible future storyline (once all the kids grow up)they want to keep the story open, so that later on they can show that Pia's child finds out that he is Jai Walia's son and then wants to take revenge because Jai did not accept him.
Nikita