Welcome to... "Micro-Lesson 252"
The progression moves through a relationship of tonality between the color of "Ab Major" and "Ab Minor." The modal aspect functions around a concept called, "Modal Interchange." This involves flipping between the harmonies of both tonalities throughout the progression.
In measure one we perform the tonic major chord first, then the IV-chord appears but borrowed from the "Ab Minor" tonality. The next measure introduces the diatonic V-chord of the key, but once again shifts up a 1/2 step to the borrowed chord from "Ab Minor" tonality.
The third measure applies the II-chord from "Ab Major" along with a smooth sounding 6th interval lick to really highlight the measure. And, in wrapping up on measure four we get a real twist to the flow of the progression by ending with a relative minor's; II, V7-chord turnaround.
The chords used are all quite common, as there are no extended or altered chords. If these chords are new, take your time developing the shapes. Use a metronome to build speed and the flow of the parts. Enjoy!
Micro Lesson 252: "Ab Major" Modal Jazz Progression