Any experience of fault code P2288 (fuel pressure too high)?

[Eeyore]

Does anyone have experience of code P2288 ‘Injector control pressure too high/Injector control pressure above expected level’ on a 2.7 diesel XJ (2009)?
Having recently had my rear brake lines replaced by the garage (involving fuel tank removal) I now have this fault code putting the car into restricted performance immediately on startup. First 50-60 miles of mixed driving were fine but now this code appears.
Is this a problem on the supply fuel pressure side or on the leak off/return side and where is the sensor that will be measuring it?
It could be totally unconnected, but I’ve never had this issue before so I’m thinking maybe it’s too much of a coincidence not to be somehow related to the tank removal/refitting?
The car has been back into the garage and they are confident that none of the pipes around the tank are damaged or restricted.
My iCarsoft i930 scanner live data tells me that the ‘fuel pressure’ fluctuates between 30,000 -44,000 Kpa at idle if that’s relevant at all to this.
Any advice on where to start looking would be appreciated please!