Conditional Formatting - based on two ranges

All,

Got a hopefully fairly easy conditional formatting I'm trying to apply, which is obnoxiously evading me. Here's the scenario.

I'm trying to apply highlighting to column L based on the following conditions (i.e., highlight if): cell in column L ='s "P" and cell in column I ='s <>"Y".

Ideally this would be in descending, so it's always looking for descending values, e.g., Highlight L3 if L3 = "P" and I3= <> "Y", Highlight L4 if L4 = "P" and I4 <>"Y", Highlight L5 if L5 ="P" and I5 <>"Y", etc.... into perpetuity (no more than 1000).

How would I code that?

Note, sample book attached but been scrubbed for confidentiality purposes. Although the columns are all in the order they should be.

Thanks in advance.

J