Oil Leak 440 driver side valve cover area

I have been swapping gaskets on the driver side valve cover thinking that it was the gasket that is the problem. Problem went away and tonight came back - I noticed the following:
Light mist residue on top of the valve cover, and around the plug wire, top of the header and around second valve cover bolt (lower) from the front. Nothing from the bottom of the cover. I looked at the dipstick and found oil in the top aeround the seal. I notice that the only time the leak occurs is between 2000 - 2500 RPM - when I am running on the highway. I belive my dipstick is the culpret - maybe backing out because of preasure or maybe the seal is shot. Has anyone ever had a similar issue?

you may have blow by as well. check your breathers, or if you do not have them on both sides you may need them.

I read a number of the threads on this and I saw a lot of feedback.
What is a good quality breather? I go have one of the Mr Gasket that have the hose attachemnts that go to the back of my air cleaner - should I lose that and go to something else?

I also will check and see if I am pulling any suction from the PCV valve - is there one that works better than others? I have a (440, and eddelbrock 84 cc heads, Comp Cams Hydraulic roller and a 6 pack set up).

I am running baffles already.
Thanks

Stick with the pcv system. Breather on one side pcv on the other is correct.

IDK what you would call a good quality breather. K&N makes some nice ones. I just run the pcv on one side and have a mopar performance breather on the other. It is nothing fancy. Has a chrome body with a foam insert. I have changed it once since I am sure it gets dirty at some point.

Check the pcv for proper operation too.

If it is the valve cover I like the fel-pro rubber coated felt. If installed right they really last even with manifold heat baking them.

My dipstick used to back itself out. turns out that the dipstick was too long. I cut off 1/2" and now it stays in place.