Chief suspect Fouad Belkacem stands accused of recruiting youngsters to go and fight in Syria. He risks a 15 year jail sentence.
The delay is necessary because the verdict is not yet ready and is now only expected on 11 February.
Meanwhile, still in Antwerp a judge has extended the arrest warrant against Jejoen Bontinck, a Belgian who returned home after joining insurgents in Syria.
He was detained at Brussels Airport last Sunday as he had teamed up with his girlfriend despite a court order to sever all contact with her. The couple say that they wanted to holiday in Turkey. Jejoen Bontinck is a key witness in the case against the Sharia4Belgium defendants.