Delta is cautious about adding more flights to its schedule due to spikes in coronavirus cases through the southeast and southwest of the United States, CE Ed Bastian said in an employee memo on Thursday. "The continued growth of the virus through the Sun Belt, coupled with quarantine restrictions being implemented in large markets in the northern part of the country, give us renewed caution about further schedule additions at this time," Bastian said. His comments raised questions as to whether Delta may pull back some of its summer flying. It has added 1,000 flights in July and another 1,000 this August, but had already said it was unlikely to add many more for the rest of the year. Its July schedule is still only about 30% of what it would normally fly. Delta is among U.S. carriers that have boosted liquidity and cut costs to stem a daily cash burn, but they need revenue to recover and will need to shrink in size as they wait for demand to return. Bastian again warned the recovery "is likely to be lengthy and slow" and encouraged employees to sign up for early exit packages by a July 13 deadline to minimize involuntary furloughs in the fall.<br/>