Hi Steve,
At an interim service I would expect a full check on all fluid levels, including screen wash and top up where necessary. Battery, steering and suspension should also be checked, and I would also expect exhaust and tyres too.
Possibly some garages would also change one engine oil and filter. Some oils are guaranteed for two years.
They will also stamp the service book, but I think a note from the owner saying that he/she has done that job using Jaguar recommended fluids should suffice.
I would also expect a full report on any faults found and recommendations on what to do.
Regards
Peter.