Well, they were expected to get out first because they commitments in Kyunki, and they are the oldest couple (on screen) among the 7, they need there proper rest, after all actors are normal people.
Basically Hiten and Gauri participated for name sake, so the fans can get a glimpse of them. That's a bumper, they should have wait for season two, and EK should have gotten a couple that had free schedule.
All the actors now when their elimination is going to happen, because like serial they are signed in for certain time period. The first fews epics shows which are the popular couples, and then the judges, the creatives tally who will get eliminated or not.

It's EK show she knows what she is doing, almost all the couples are from her show. Gauri and Hiten are mayis favorite couple who she can't scarfice for Kyunki, as she knows that members watch to get glimpse of Karan and Nandhni.