Not that long ago, if you made an airline reservation, and then had to cancel it, you risked losing what you paid for the ticket with extremely high ticket change fees.

Then, during the pandemic, U.S. airlines eliminated those draconian fees in an attempt to stimulate travel.

Beware of the law of unintended consequences. Smart travelers are now doing something called trip stacking — booking multiple trips during the same time period — to hedge their bets as COVID-19 rules keep changing at destinations around the U.S. and the world.

They are keeping their options open, making ticket reservations on multiple flights to multiple destinations — and then cancelling two out of three without financial penalty as destinations open up.

But here’s one caution. Many hotels and resorts still have rules about non-refundable deposits.

Before you do any trip stacking, make sure you have an agreement with the hotels about refund policies and cancellation fees.