This looks like the second update of the Sanctuary of the Christian Science Church in Denton. I found a drawing dated 2/1991 shown below. The ceiling about the podium is raised to match the slope of the auditorium and the Hexagon shape is added. There is also a new larger podium lectern added. The entrance to the podium is moved from the back wall of the podium to the side wall.
From what I could gather, it seems that the church was growing and instead of building a larger building they removed the theater style seats and added pews to accommodate more people in the same space.
The Leslie speaker is still there on the left side of the podium (flowers on top of it ). It remains in the church today but it is no longer connected to the hidden organ.
In order to add lighting to the sanctuary, 6 new sconces are added to the side walls.
Here is the plan adding the pews and removing the theater seating. There is a addition of two readers rooms and an Organist/soloist room that was not ever added. Notice that a stain glass window was proposed on the back wall of the podium.