Next time you're under your Jag, look at the left rear side of the transmission, following the shift cable housing to the shift cable anchor plate. This plate is held to the trans housing with two 6mm cap screws (with 8mm hex heads). You may find that they're loose. Suggest remove one at a time and replace with a drop of red loctite. Torque 'em to ~ 60 in lbs (snug, with a little 8 mm wrench)
This may save you a towing bill and a really bad day

(My console shifter became hard to move ('07 XJR). Turned out to be a piece of loose plastic jamming the J gate moving cover. But, I crawled under the car first to check the shift cable, and found the cable anchor plate loose. Just a matter of time before it left me stranded... Loose anchor plate symptoms may be stuck in park, imprecise lever position or stiff lever movement, but suggest don't wait 'til then)

 

Good advice ... over the past few years a number of people have reported those bolts coming loose.