Many folks are aware of this I'm sure, but I just ran across one, and thought I'd pass it along for those that aren't.
S-Types and X350's all have an undertray below the engine. For some reason, [and I have yet to get that reason] Jaguar tacked to that undertray a plastic, foam filled pillow. That pillow traps a horrendous amount of moisture and lays against the steel front cross-member and harbors corrosion, lots of it! Consequently, any such car that lands in front of me has that pillow removed. I then treat the member with an anti-corrosion spray. The damage is usually done, but hopefully it helps. Those cars that I caught early, I'm happy to say, show very little corrosion, even at higher mileages.

Examples are attached. Those that have these models would be smart to check this area out.

 

probably a noise abatement feature

X308 affected?

 

No, thankfully they don't have a full undertray.

Cheers,