Final update !.
So, I got a call from the service manager at the dealership today to ask if I would like to see inside the gearbox now that it has been opened and cleaned. I said yes and went along this morning.
Okay, so the visible damage even before they began stripping out the components was severe. There were metal splinters the length of your pinkie nail and extensive scoring to the gears themselves. There was a chip out of a reverse gear tooth, (which explains the car jumping out of reverse) and the metal contamination in the oil was like a child had just poured glitter into it.
They were talking about trying to replace ALL of the internals in the gearbox, to which I said, NO !. I pointed out the minimum I would accept would be a factory sealed brand new gearbox, but that my preferred option was to reject the car.
I spoke to the general manager and pointed out that under the Consumer Rights Act 2015, they had now exhausted their one attempt at repair or replace as they had ordered 3rd and 4th gear syncro cones as the final fix and that had now failed to resolve the issues. They have also had the car for nearly 4 weeks and any additional fix would be an open ended timescale.
So, they have now taken the car back and given me a full refund. A like for like replacement isn't an option for now as there appear to be a large number of defective gearbox's that have been fitted to recent 595's and there is no guarantee that any replacement wouldn't be faulty.
Additionally, the dealership are at present unable to order any new gearbox's from Fiat/Abarth as they are all now showing on their system as being reconditioned. I wonder why...
So, basically I'm left now looking for another car. Back to thinking about that new Civic Type-R I guess...