Well, the idea of cruising to New Zealand and staying for a while afterwards in January 2022 is now looking a bit risky. A day or so ago, murmurings started from the Government that overseas flights might not even start again until next year. This would mean that getting a flight back from NZ after the cruise could be a serious challenge - we would always have been competing with the 'end of school holiday' crowd and now unless the NZ bubble was properly in place before-hand we'd be competing with huge numbers of people who just wanted to see family and friends again after this very long period of being unable to do so.
Problem solved - I booked another cruise. As well as the 18 January cruise from Sydney to Auckland we're now also booked on the next cruise which is from Auckland back to Sydney. The cruise back is a slightly different itinerary which includes Picton and Wellington instead of Christchurch and Melbourne.
Of course we still have no idea if cruising will have even restarted by January. This just means that if cruising is okay but flights are a problem, we'll be able to get home. And since the cruise lines are currently being far more generous than usual about their cancellation fees, we have until December before we definitely need to make a decision.
