5.3. Where a developing country or least developed country Member considers that it requires a
first extension longer than that provided for in paragraph 5.2 or a second or any subsequent
extension, it shall submit to the Committee a request for an extension containing the information
described in 5.1 b. no later than 120 days in respect of a developing country and 90 days in
respect of a least developed country before the expiration of the original definitive implementation
date or that date as subsequently extended.