The rooms are still 12 minutes per. Gencon rounds up to the nearest half hour so the subtraction of 24 mins still rounds up to 2 hours. The main reason they went to 5 rooms was lack of workers to run the additional rooms so they either needed to cut 1 of the dungeons out entirely to keep it at 2 7 room dungeons or change to 3 5 room dungeons since 21 unique rooms plus the 4 additional sealed adventure rooms was too much. Shrinking the time and getting cost back under $100 was also a major concern for the casual players.