7 1/2 Hours is a long time to make a decision to cancel the flight.
It wasn't like the flight just sat for 7.5 hours and then cancel, several attempts were made to get it out but it was just a series of unfortunate events.
Skd departure was 1059
Departed at 12noon
Air return about 1 hr 15 min later
Pulled into the gate at 1320
Gave out $10 meal vouchers to pax as they came off a/c
Found new a/c at hanger to replace it with, (tail 908)
Pilots timed out, called new ones
Passed out bottled water and snack packs at gate
Pilots arrive at new gate at 1550
A/C comes over from hanger 20 min later
Flight re-boards on new a/c
MX issue comes up after all pax boarded during flight deck pre-flight check list
Capt would like to MEL issue and take flt out, but policy won't allow MELs on ETOPS flt
Find third a/c that can take out flt but it is enroute from CUN and wont arrive till 2055
FAs time out - tried finding reserves to replace with but all have been used up
Flight cancels at 1830
Everyone did everything they could to get the flight out, sadly it just was one of those things where we fixed one problem and then another pops up. Passengers were pretty calm and understanding with the agents knowing they weren't the ones responsible for all the issues save for the typical few. A few pax even went out of their way to tell agents how well the were taking it all.