The Danish defender was outstanding in the Reds' play-off campaign last term and was an ever-present in the Championship.
But he has been sidelined since pre-season with a knee problem and while Schopp is pleased with his rehabilitation work, he won't return to the fray until the autumn.
Schopp, whose first game in charge at Oakwell is against Coventry City on Saturday, said: "He is doing great. But it will still take a couple of weeks, I guess.
"Hopefully, we will have him back after the break. That would be awesome. But we don't have a date.
"He is a really important player for us and to get him back will be a big thing for us."
Despite intimating on Tuesday night that recent arrival Obbi Oulare could be available for the home game with the Sky Blues, Schopp says that Tuesday's encounter with visiting Luton is now looking more likely.
"We can talk about this situation right now and he will not be available for tomorrow, so we are looking forward to getting him for the next game on Tuesday," he commented.
Meanwhile, Schopp has confirmed that there are no fresh transfer developments at Oakwell, with activity likely later on this month, heading towards the transfer deadline.
He added: "There is always talking between me and the board to get things forward, so it is absolutely our intention to move in the market. But we know we are Barnsley, so we have to take care as to which options we have and then we have to be well-prepared.
"We want to be a bit more flexible in a few certain positions and that is the way of my thinking and what I am thinking of moving forward. It is up to us to find a good solution and I guess it will be more at the end of the transfer window."