Even as the world opens up, Covid-era travel remains complicated. The rules for travel are constantly in flux, and different everywhere you go.

• Do you need to be vaccinated? What counts as proof? And which vaccines even count? How long is your vaccination valid, and is one dose enough if your vaccine was approved for a two-dose regime?

• Do you need to be tested if you’re vaccinated? Do you need to be tested if you haven’t been vaccinated? If you’re traveling with children for whom there’s not yet an approved vaccine, are they welcome into the country, and do they need to be vaccinated?

• What tests are eligible? Can it be a rapid antigen test, or does it have to be PCR? Is there a list of providers you need to stick to for your test? What if your airline is offering tests, but those tests aren’t from a provider listed on the destination’s website?

• How far in advance of travel does the test need to be taken? What’s the difference between a 72 hour requirement and a 3 day requirement?

And as if that isn’t enough, you need to worry not just about your destination but about connecting cities too – because flights delay all the time, and you might misconnect. You don’t want to be stuck in the airport overnight.

You need to be prepared to stay at your destination longer than planned if you test positive, too, and that could be more likely than you’d think if you’re talking a lower-quality antigen test. Or you need to build time for possible re-testing into your plans.

What happens when rules change while you’re in transit? That doesn’t happen all the time, but it does happen. For instance:

• A planeload of Virgin Australia passengers were forced to quarantine because state entry rules changed while they were in flight (and that wouldn’t have happened if their flight hadn’t been delayed).

• Last summer passengers off a Qatar Airways flight were forced into quarantine in Italy because while the passengers were in transit rules for entry by Bangladeshis had changed.

I call the rapidly changing rules around travel during coronavirus regime uncertainty and it’s rules that change after you buy your ticket but before travel, or even while you’re in transit, that make everything complicated enough to deter travel even if you overcome the cost and hassle.

In another shocking example, an Indian airline sent its crew on a flight to Croatia with confirmation that they would not need PCR tests to enter the country. By the time plane landed in Zagreb that had changed, according to the carrier.

• Crew couldn’t enter the country for their required rest
  
• They couldn’t get tested in the airport on arrival
  
• And so they were forced to spend the night on the plane

The time on the plane didn’t legally count as rest to be able to fly home the next day, either. So an accommodation was made between the airline, crew, and regulators. The plane flew home with 3 pilots in the cockpit, and no crew or cargo could be on onboard. (HT: One Mile at a Time)

Fortunately the airline got its act together with a successful flight back to Croatia after this incident.

Guess we hit the bullseye with this special flight. We had the pleasure of flying India’s shooting contingent to Zagreb, Croatia, where they are scheduled to participate in the European Championship later this month. Good luck with your Olympic prep, team! @Tokyo2020 awaits!(1/2) pic.twitter.com/5WI4mZq4X3

— SpiceJet (@flyspicejet) May 14, 2021

It’s possible that the airline made the error, though they claim to have written information from Croatia confirming their crew wouldn’t be tested. But that’s also the point. If an airline can’t keep this all straight, what chance do passengers have, even with the assistance of their airline and third party apps? Much of the time this works out fine, but occasionally things go wrong and when they do the downside is significant enough that this deters plenty of travel.