As you can see from Jordan’s Freshman year signatures at UNC, he seemed to be testing out numerous different types on different media (balls with the non-cursive J were different from posters and other items). 

From all of my research, it seems during the summer of 1982 after the NCAA Championship, that he worked hard on creating a more consistent, recognizable signature and one with more style.   From the 1982-83 UNC season, you can see the differences from his 1981-82 versions with a significant variance and extra “flare”.  

In these versions, especially on team signed basketballs, his signature is definitively larger, more elongated top to bottom and the "M" and "J" have started to display elements that would continue on throughout his career.

As you’ll see in the 1982-83 signed ball owned by Wesley Gretah below, the signature has turned into quite a brilliant signature style.  Both the "M" and "J" would start to feature the figure 8 at the base of the strokes in each, while both of those have become much more impactful in the overall signature.  The final "L" stroke in Michael has turned into the curved flare style that will be showcased for a few years.  Luckily, most of the letters in his name are still distinct and as seen in most Jordan signatures, the "n" is virtually non-existent.  

If you compare this to 2 other signatures examples from the 1985-87 era, you can see the similarities and how the flare has been added.