20.89Ending

Simple:

Cm7 → F7 → B♭6/9

Turnaround tag:

B♭ → G7 → Cm7 → F7

repeat phrase

then B♭6/9.

Chromatic:

Cm7 → B7 → B♭6/9

where B7 can act as a chromatic dominant-like approach depending voicing/context.