you dont need 20 players... cause when it comes to waiver wire pickups.. they wont need to drop anyone.. where is if you are at the max.. to pick up a guy on waivers you need to release someone.. good strategy by the canes..
The 20-man rosters are for tracking salary cap during free agency.
During free agency you need to account for at least 20 players and their salaries. Canes are three short of that, they need to include three more players.