There is a legal requirement for the freeholder to grant a lease extension of 90 years (in addition to the 66 years left). This is known as a statutory lease extension, see here for more details and the steps that need to be taken:
http://www.lease-advice.org/legsframe.htm
Because the unexpired term on this lease has dropped below 80 years, marriage value will be taken into account when the surveyor employed to do lease valuation does his calculations.
The freeholder can grant a lease extension to your friend outside the terms of the 1993 Act, but if they are dragging their heels, then your friend can take the statutory route.