Does Ekklesia always mean a church with pastors, bishops, and deacons?
No. Ekklesia in its true translated form means a called-out assembly. It does not necessarily denote a church with pastors, bishops, and deacons. That meaning fits when Paul speaks of the Body of Christ in the local church. Elsewhere it can describe Israel in the wilderness, Jewish believers in Jerusalem, or even a rioting mob in Ephesus.
Les explains that Ekklesia was a called-out assembly. It does not mean someone with pastors and bishops and deacons necessarily, although when Paul speaks of the Body of Christ in the local church, yes it does. The same word is used for the Church in the wilderness in Acts 7, where God called Israel out of Egypt unto Himself. The Jewish believers in Jerusalem were also an Ekklesia because they separated from the run of the mill of Judaizers, though Les maintains they were not yet the Body of Christ. In Acts, the Ephesus mob rioting in the theater was also called an Ekklesia; the King James translators rendered it "assembly," not "church." Les prefers the word "assembly" because that is what it was, and he warns not to let these terminologies confuse us or set us straight.