In reviewing the "Passport to Service" section of the owner's manual for my new F-Pace, I was surprised to see 2 year or 21,000 mile intervals between oil/filter changes. My understanding was synthetic oils last a year or 10,000 miles. Is anyone actually following this?

I just changed my wife's F-Pace SVR at 4500 miles. I can't wait that long, and I drained from the drain plug. I know they suck it out at the dealership, but I figured draining it would remove more of any debris that might be in the sump.

What do you think is the motivation behind the long interval? If synthetic oil lasts up to 10,000 miles, why go beyond double that number? Especially on the first oil change after the break in period.

I have no idea. It seems extremely long. If I understand right, the SVR's call for a 12,000 mile / 1 year oil change. Still too long for my brain on a 100K vehicle.

The JLR engines in the land rovers have been on a 16,000 mile interval for a while now. It's very common for modern engines and oils to be on 15000-20000 intervals. It's a myth that somehow oil breaks down after a year or 10k miles

If in doubt you can test the oil after 15000 miles and analyze its condition.

That said an oil change is cheap and easy (if you do it yourself) so is good peace of mind for some. But manufacturers have tested extensively and do not believe that's needed any longer.

It's not so much the oil breaking down but more the build up of sludge and carbon deposits in the engine that suggests more frequent oil changes are a good idea.
Even more so on the direct injected AJ133 and AJ126 with their problematic (at least in the early versions) timing chains and tensioners.
For that reason I change the oil every 3,000 miles or so, maybe overkill I know, but I do only some 3,000 miles a year anyway with mainly very short trips (bad for the oil) and the oil is relatively cheap and a doddle to change so I consider frequent oil changes to be good insurance.
Also these days there seems to be some sort of competition amongst car makers as to who can give the longest specified oil change intervals, dunno why but maybe so they can claim "our service costs are cheaper than the others".

And condensation.

I do the same as well. I plan on purchasing a F Pace SVR so I want to keep it well maintained. Just started looking today