Select Same Subpositions ⇧P – Logic Pro keyboard command of the day

  Select Same Subpositions   ⇧P

With an event selected pressing Shift-P will select all of the events that start at the same position in a bar. If there is only one event at that position the currently selected event is de-selected.

Very useful for editing notes.

Select events in the Logic Pro Event List – Apple Support

Same Subposition (or press Shift-P): Selects events that start at the same position within their respective bars.