156 potential rust issue

[MarkwG]

Applogies if this is old news. Our venerable Sportwagen is approaching double figures & during the post winter de-cacking, I noticed the rubber seal which stretches up the A pillar right along the roof/side panel to the tailgate felt a bit weird - crunchy, not sitting right. In for a penny, etc, I whipped it off to unveil tin worm gnawing on the metal work, where the roof panel joins the side panel. Not exactly "a month in the sea" state, but starting to eat away at the edge. A dose of rust killer & some Hammer type paint, & the rust is sorted, but the metal gripper on the seals is pretty done for, so planning on replacing those. The inner metal seems to have had it, such that it won't properly tighten down.
It's not a whinge, ten years in this climate & I'm not surprised, & it's possible it's a one off; but you may want to have a sneaky look at yours, just in case. I imagine long term, the roof & side panel work would start to separate & at the least, let water in. If anyone has seen this posted elsewhere, drop a link & I'll delete it.