So I noticed that they had fitted the oil feed with both crush washers on the bottom rather than one either side of the banjo
The leak is not from the top but I assume they did the same on the other end. Anyway, I supplied a new return pipe and pointed out the crush washer problem and got the car back with no oil leak. I took for a long drive but got an engine light. The codes are
P0139
P0299
P0054
I am thinking that perhaps the o2 sensor got dirty during the fix and this caused p0054, with the others being ghost codes.
I have cleared them all and will see what happens.