Conn. Agencies Regs. § 31-237g-27
In any case where the Referee's jurisdiction over the appeal appears to be the preliminary issue due to questions concerning the timeliness of the filing of the appeal, the aggrievement of the appealing party, mootness of the appeal, or any other reason, the Referee shall schedule a hearing upon the appeal but may (1) limit the hearing to such jurisdictional issues and thereafter issue a written decision limited to such issues, provided the Referee shall schedule a further hearing to take evidence and testimony on the remaining issues in the event that the decision rules that the Referee has jurisdiction over the appeal, or (2) schedule a full hearing on all coverable issues and thereafter issue a decision, provided that if the Referee rules that the Referee lacks jurisdiction, the decision shall be limited to the issue of jurisdiction.
Conn. Agencies Regs. § 31-237g-27