And, if he's already at the throne, then he would have entered with his mandia before the reading of the psalm right?
Just trying to make sure...as many details as you can remember (or find) would be most helpful.
If it is the Vesperal Liturgy the Bishop is fully vested before the start of Vespers and is outside (in the Greek practice, always at his chair). During the entrance and at "now that we have come" he descends his chair and goes to the middle of the Solea and begins to bless the four corners. At "Father, Son and Holy Spirit" the Bishop enters the sanctuary.
This is what I remember also.