<h1>IndiGo flight cancellations tied to new FDTL rules prompt regulator show-cause notices and temporary relaxations for airlines.</h1> Regulatory show-cause notices were issued to the carrier's chief executive and accountable manager for alleged planning, oversight, and resource management lapses amid mass flight cancellations attributed to phased implementation of new Flight Duty Time Limitations-norms that increase weekly rest, extend night hours, and limit night landings-while the regulator granted time-limited relaxations and extended the deadline for the managers' replies.