Recommended tyre pressure levels depend on the engine & body type, not on the tyre size.
SEAT recommends same levels for all tyre sizes in a specific model, engine & body type combination.
I have the
maintenance handbook for Leon Mk4 on hand, and it shows all tyre label contents, of which there are 14 variants with distinct part numbers.
If you don't mind sending me your VIN via a PM, I can find the exact tyre label that was in your car and its contents.
Edit: 245/40 is not the official size for 18" wheels, in case you're not the one who replaced the original tyres. Factory mounts 225/40s on 18s.