First thing is to check the valve covers,sounds like the one that you used to re-fill with
oil after your
oil change is "seeping".......
I doubt it's from your front crank seal, if it was the source of the leak, it would POUR
oil with the engine running.....
Being the leak is only when the engine is not running, leads me to think something needs tightening and I'm betting a valve cover.....
David