They're not unreliable, they're travelling blind.
Same thing for us continentals with the RWD LR some time ago: they only started to assign VINs (in Fremont) about a week before the first ship that had those arrived in Zeebrugge. The ship had loaded RWD LR in SFO even though that was not an on-menu choice. The SR+ on-menu choice was not on the boat at all ;-). Makes perfect sense...
No one in Europe knew exactly what was on the boat, and they usually told you they had no information. If you tried to press for more information, then you'd simply get unreliable information (I was told that my car was 100% surely not on the Monring Cornelia, but guess what happened when they started assigning VINs from that ship to orders...). Sometimes people on the phone would make wild guesses in a well-meaning attempt to please you...same thing.
Mind you, I had to call in every time something happened in my account just to find out a VIN had been assigned ;-).
Now if you want a RWD LR you have to wait, except if you want one with a towbar. Because it turns out the ship had some towbar-ready cars when it was sailing here, even though the feature was not yet announced to be orderable, so there are a few left...and they're actually phoning around to see if someone doesn't want to add a towbar to his order.