June 27 (Reuters) - Airlines canceled nearly 700 flights in the United States early Monday, as they struggled to keep up with a surge in summer travel demand due to a shortage of staff ranging from pilots to crew members. Total flight cancellations within, into, or oislot88 out of the United States as of 6.07 am ET were 669, as per flight-tracking website Flightaware.com website Nearly 860 flights were...
