# Requirement change

Revenue want a lever pulled before the weekend: once a show is filling up, later seats should cost
more. Nobody wants a dynamic-pricing engine — just one rule, live today.

**Once half of a show's seats are booked, every seat quoted from that moment on costs 20% more.**
"Booked" means booked — a seat somebody else is merely holding does not count toward the halfway
mark, only a confirmed booking does.

The price a hold quotes is still the price the booking is charged, whatever happens to the show's
occupancy afterwards. If a hold was quoted before the show crossed the halfway mark, confirming it
later still charges the original, non-surged price — the surge is about what gets quoted from now
on, not about retroactively repricing somebody who already committed.

A worked example, so nobody has to guess the rounding: MATINEE has six seats, so the moment the
third one is booked, the show is exactly half full and the surge switches on for every seat held
from that point forward, whatever type it is. A standard seat that was 500 before is 600 from then
on; a premium seat goes from 800 to 960; VIP from 1200 to 1440.

Nothing else changes: the base prices, the all-or-nothing rule for a group hold, HOLD_TTL, and
every exception all stay exactly as documented.
