Authorities are allowing standard tickets to the World Expo 2010 in Shanghai to be upgraded to peak tickets for entry during the National Day holiday, which runs from September 30 to October 7.

The move, announced Monday by the Expo Coordination Bureau, is aimed at allowing those who acquired their tickets at non-peak prices to still be able to visit the Expo over the holiday period by paying the difference in face value between the tickets they hold and the peak-time tickets.

Over the holiday period, single-day admission tickets cost 200 yuan ($30), compared to their usual 160 yuan ($24); while single-day special admission tickets for students, the disabled and the elderly will cost 120 yuan ($18) compared to their usual 100 yuan ($15).

Three-day and seven-day tickets can not be used during the holiday period.

People wishing to upgrade their tickets will need to visit one of the ticket offices at Bailianjing, Gaoke Road West, Changqing Road, Shangnan Road, Houtan, Luban Road, Xizang Road West, Bansongyuan Road, Madang Road or Dongchang Road.

Tickets can be exchanged on the same day as entry from 8 am to 8:50 pm, while tickets for the next day can be exchanged between 4 pm and 8:50 pm.

"Holders of standard tickets were worried that they would not have enough time to visit the Expo," Pan Jieren, an official from the Expo Coordination Bureau, said. "The new policy will enable them to visit the Expo during the National Holiday."

Since September 22, holders of standard single-day tickets have been able to exchange them for two evening admission tickets for no fee.

Expo tickets will also be charged at a peak rate for the final week of the event. However, it has not been announced whether standard tickets can be upgraded for this period.