Per above...no, this isn't force majeure. If CX had to (
for example) cancel all flights in and out of Hong Kong then
that would be force majeure. If a bunch of planes were unflyable because of an outbreak of coronavirus among the crew, that might fly. But CX is citing "commercial and operational" reasons.
Honestly, there are things they
could be doing even if the email system is overwhelmed (posting a list of cancelled flights by day on a dedicated webpage comes to mind).
@
AlwaysOnTheRoad: You said that CX cancelled your flight day of departure and put you on a flight a day earlier. Do you mean to tell me that you were cancelled out and put on a
previous day's flight?