Fast-food customers are back, but workers are not. It’s triggering major change.

At Yum Brands, revenue soared 34 percent, to $1.6 billion, in the most recent quarter — momentum that CEO David Gibbs said was underpinned by the Louisville-based company’s digital investments and “ability to serve customers through multiple on- and off-premise channels.” In a July 29 earnings call, he noted that digital sales, including online orders for pickup and delivery, are up 35 percent year-over-year. Meanwhile, roughly 1 percent of its KFC stores and 2 percent of its Pizza Hut locations were temporarily closed at the end of the June, according to its earnings report.