Guys! I just saw the SBS video. (https://www.indiaforums.com/forum/topic/1043396 -> segment 2)
And honestly what Ekta has said is very ambiguous. I don't think we should jump to conclusions yet until Harshad himself confirms it. I think that Ekta might have been speaking about Harshad's departure from Mahabharat.
What she says is that she has casted Harshad in a new show, and it wouldn't have been possible for him to shoot in "both" shows simultaneously. Although she does mention harshad "leaving" KDMHMD, she makes it sound as if he would have had to leave (like as in for a trip or something) in that show so that he could give dates for her Mahabharat.
Also, this interview was done when she was doing the press-meet for Mahabharat (she's wearing the same outfit, and you can see Hiten in the background), and it wasn't anything related to KDMHMD.
Honestly, I just think that her interview was blown out of proportion. Think about it: why would she kill off her main character when Premheer is what makes KDMHMD -> especially since that is the only show of hers that has been giving competition to Bidaai – a show that has been topping the TRPs since like 2 months now.
Also, with the new Sanjana angle, I do not think that Ekta's going to kill off Harshad, when she stretch the story for all it's worth.
I hope I made sense in my post. Actually, I was at school when I read the article about Harshad leaving, and I was so panicked.. and I only had time now (I couldn't sleep.. I was so depressed.. it's past midnight for me) and I decided to do some "research" on why he might be leaving. (ahah.. I can't help itt..Harshad's taken over my life) and after I saw the SBS video, I was so much more revealed!
I hope this puts you guys at ease as well! =)