=IF(AND(ISBLANK($G$11),ISBLANK($O$11)),TRUE,FALSE)
=IF(AND(($G$11<=20),ISBLANK($O$11)),TRUE,FALSE)
=IF(AND(AND(($G$11>20),( $G$11<=50)),ISBLANK($O$11)),TRUE,FALSE)
=IF(AND(AND(($G$11>50),( $G$11<=100)),ISBLANK($O$11)),TRUE,FALSE)
=IF(AND(AND(($G$11>100)),ISBLANK($O$11)),TRUE,FALSE)
=IF(AND(ISBLANK($G$11),( $O$11<=7)),TRUE,FALSE)
=IF(AND(($G$11<=20),( $O$11<=7)),TRUE,FALSE)
=IF(AND($G$11>20, $G$11<=50, $O$11<=7),TRUE,FALSE)
=IF(AND($G$11>50, $G$11<=100, $O$11<=7),TRUE,FALSE)
=IF(AND($G$11>100, $O$11<=7),TRUE,FALSE)
=IF(AND(ISBLANK($G$11),( $O$11>7), $O$11<=30),TRUE,FALSE)
=IF(AND($G$11<=20, $O$11>7, $O$11<=30),TRUE,FALSE)
=IF(AND($G$11>20, $G$11<=50, $O$11<=30),TRUE,FALSE)
=IF(AND($G$11>50, $G$11<=100, $O$11>7, $O$11<=30),TRUE,FALSE)
=IF(AND($G$11>100, $O$11>7, $O$11<=30),TRUE,FALSE)
=IF(AND(ISBLANK($G$11),( $O$11>30), $O$11<=60),TRUE,FALSE)
=IF(AND($G$11<=20,$O$11>30, $O$11<=60),TRUE,FALSE)***
=IF(AND($G$11>20, $G$11<=50, $O$11>30, $O$11<=60),TRUE,FALSE)
=IF(AND($G$11>50, $G$11<=100, $O$11>30, $O$11<=60),TRUE,FALSE)
=IF(AND($G$11>100, $O$11>30, $O$11<=60),TRUE,FALSE)
=IF(AND(ISBLANK($G$11),( $O$11>60)),TRUE,FALSE)
=IF(AND(($G$11<=20),( $O$11>60)),TRUE,FALSE)
=IF(AND($G$11>20, $G$11<=50, $O$11>60),TRUE,FALSE)
=IF(AND(($G$11>100),( $O$11>60)),TRUE,FALSE)
=IF(AND($G$11>50, $G$11<=100, $O$11>60),TRUE,FALSE)

The columns with "TRUE" or "FALSE", only represent the formulas that I would use for the formatting. In reality they would be TASK's i.e. "Replace Oil Filter"