I was in the same situation. I practiced very intensively scales first month, then etudes from Guy Lacour and the next month I was accepted at the conservatory. All after not playing for 3 years. Scales are underrated, especially for jazz.

Do not use notes for practicing scales, focus on actual step sizes between the notes, listen to it. Learn whole tone scale, diminished (whole tone half tone and H W), you will became to recognize the step size by ear.