Every time I hit a bad bump or change in pavement at highway speeds I hear an annoying squeak or chirp from the drivers side B-Pillar (the pillar that separates the driver's door window from the little triangular window behind it.)

The dealer has made two attemptsto fix it, and it does occur much less frequently now, but it still happens when I hit a bump or change in pavement at highway speeds. It's very annoying. I have the CPO warranty and wonder how far I can go in exerting a claim.

Can anyone offer insight/experience of the same.

Sorry, none.
I haven't even been inside the B-pillar of my P-car yet.
You said the noise was reduced after the dealer messed with it? Exactly what did they do?
Have you tried using a dab of silicone on the tabs/clips? Maybe one of the clips is loose.

That's my stab in the dark.