I think a few lines will be watching.
As well as P&O, I can see the following ships with Noumea in their schedules for example:
Oct: Westerdam, Quantum OTS
Nov: Quantum OTS, Ovation OTS
Dec: Carnival Splendor, Majestic Princess, Celebrity Eclipse, Quantum OTS, Ovation OTS
If the Pacific Islands are off the table for longer than they might have to scramble and reschedule some cruises, or maybe even redeploy a ship or two 😞