The 2010 S/C petrol has the 6HP28 box and full 2010 CAN bus with the later 29 bit addressing. However, most 2010 petrols did not come with paddles as standard. These are the ones which can be retro fitted, sometimes needing a firmware mod to the gearbox. The 2011 to 2013 petrols had paddles fitted as standard but did not get the 8 speed box until the L405.

The 2010 3.6 Diesel has a 6HP26 (which is ostensibly the same internals) but I believe it has the older ECU and the older (2006-2009 11 bit) CAN bus where the paddles are unable to communicate with the gearbox over the CAN. There is a mod to wire the paddles into the command shift but this involves much soldering and running of wires - someone on here has done it, but NOT via the CAN.

The diesel model did not get the newer CAN until the arrival of the 4.4 TDV8 and these came with paddles as standard. That came with the 8HP70 (8 speed) gearbox which has the newer CAN connected ECU.

The 2009 model (sometimes sold as a 2010MY) 3.6 diesel is a real mongrel. Later LCD dash, non-Brembo brakes, old CAN bus, old gearbox. A real bitsa. These models cannot have the paddles retro fitted, well not to work over the CAN anyway as far as I am aware.

That's my understanding anyway and I've not seen exceptions to the above