Data storage device dynamically generating extended redundancy over interleaves of a data track

A data storage device comprising:

• a disk comprising a plurality of data tracks, where each data track comprises a plurality of data sectors;
• a head actuated over the disk;
• and
• control circuitry configured to:
• generate a first codeword comprising first redundancy;
• generate a second codeword comprising second redundancy;
• write at least part of the first codeword to a first data sector and a second data sector of a first data track;
• write at least part of the second codeword to a third data sector and a fourth data sector of the first data track different from the first data sector and the second data sector;
• detect an anomaly in at least the first data sector of the first data track;
• when the anomaly is detected in the first data sector, generate first extended redundancy over at least the first data sector and the second data sector of the first data track without generating second extended redundancy over the third data sector and the fourth data sector;
• and
• recover data from the first data sector based on the first extended redundancy.