The Delta Queen

Can a long time Cincinnatian clear this up for me please.

QUOTE;The act prohibits wooden boats from carrying more than 50 overnight passengers.
Rep. Steve Chabot, R-Ohio, wants a 10-year exemption. "The Delta Queen is a national historic treasure, and I think it would be a real tragedy if it is shut down," he said.
Why can't they continue operating during the day? I don't understand why this is the end of the world for the Delta Queen.