Many people are wondering, if the Chapterhouse lawsuit is not yet even at trial, and the lawsuit was the issue, how did GW release these models? I have seen that many people were thinking the lawsuit did not hamper the release, but instead was a way for GW to sell more models. Well, hopefully that answers the question.
Take this with the same amount of salt as anything else that is not an official statement by the company.
Concerning the Chapterhouse lawsuit, I would be the person concerned who first bought it to light.
Essentially I was told over a year ago, by a very, very reliable source (who shall remain unnamed) that certain kits were being held back by GW as there were concerns regarding the Chapterhouse lawsuit.
GW had been advised that because they had not released physical representations of Thunderwolves, Tervigon, Tyrannofex, Doom etc that third parties who already had could contest ownership.
GW have never released a Thunderwolf model, they have released Canis Wolfborn, and as such own the rights to a model caleed Canis Wolfborn, but had not yet released Thunderwolves.
There was a fear that releasing these models after other third party manufacturers (not just CHS) would weaken their case against Chapterhouse.
The most contentious of these models being the Doom of Malantai, Tervigon and Thunderwolves.
However it is no coincidence that several months ago GW hired a new IP lawyer, who now advises them on exactly these kind of issues, and it is obvious that their legal advisors have said it's ok to release these models.
It's not a coincidence that Thunderwolves and the Tervigon have been released simultaneously just before the case gainst Chapterhouse goes to trial.
I reckon it will be at least a year if not longer before we get any resolution on that, if any resolution can ever be met as it looks as though neither side is willing to back down.
However I expect that GW is keen to win this (not that I'm saying that they will, I think they have made some howling errors tbh) if only because of license deals like the one for the Hobbit.
But I expect ChapterHouse and all the other third party companies will be trading for the forseeable future.
The general concensus is that these originally weren't going to be released together, but the schedule got messed up by some bad legal advice, and GW have been waiting for an opportunity to release them ever since.
They were well aware of the feeling of the community towards either not being released and a few months ago decided to add them into the Feb / March schedule as "birthday presents" for 40k fans.