Early during the pandemic, United Airlines added an option for flyers booked on “fuller” flights to make a change to their trip, including moving the date slightly — or even choosing an alternate departure or arrival airport nearby — completely free of charge.In general, this option became available when the check-in window opened “on flights that [were] expected to be closer to full capacity,” or at the gate when more than 70% of passengers had checked in. American Airlines introduced a similar program as well.The practice continued for more than a year. For a United trip I flew this May, for example, United sent me a text at check-in, saying: “We do expect this to be a fuller flight. To see if other flight options are available and change with no fee, go to [United’s website].“This week, I received a similar “fuller flight” text message, but instead of offering a free change, the airline reminded me of its general COVID-19 practices, saying “We’ve got you covered by putting your health and safety at the forefront of your experience. Learn more about United CleanPlus and the latest science on safe travel: united.com/cleanplus.“So, what prompted the change? With so many Americans traveling once again, most flights likely meet the “fuller” criteria — customers only had an option to change if there was a flight available with many empty seats, a rare occasion these days.A United spokesperson confirmed the shift, but noted that the airline now waives most change fees, so if you’re looking to move to a less-full flight, you don’t have to pay an extra fee. The big difference here is that fare differences are no longer waived — if your new flight is more expensive, you’ll have to fork over some cash to cover the difference.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.