If you are looking for the patch notes or trying to figure out why you need it, here is what 1.03 introduced:

Specific character balance adjustments, such as refining Talim’s air-dance or Ivy’s infinite loops.

A major goal of late-cycle patches like 1.03 was improving the online versus experience. Developers worked to reduce latency issues, which were a common complaint during the early days of console fighting games.