It is the max tire size for these rims and it looks awesome! The ride is tight, smooth and fun. Pay no mind to the charts that tell you that you cannot do it. Continental Extreme Contact Sport. I was supposed to have 265's put on the front 8.5" wheels but they have not come in yet. In the meantime they put new 255's on until they do, which should be this week. Very happy Jag owner here.

 

Makes sense.
Stock XFR rear tyres are 285/30ZR20 on a 9.5" wide wheel so going to 295 should not be a problem at all.
IMHO claims that 285 is the max width for a 9.5" wheel are overly conservative.
That said all stock F-Type rear 20" wheels/tyres are 10.5" wide with 295/30ZR20 tyres.