Warbirdsim haven't stopped trading. The site is still there, the shop is still live. The company that registered the Warbirdsim domain name was dissolved at the end of last year.
The problem is that Warbirdsim are acting in an exceptionally disingenuous and secretive way. No names, no company details, claiming to be registered as a UK company when they are not. None of that may be illegal, but it is exceptionally untrustworthy.
What worries me - as this has happened before a number of times in my experience and the man behind Ariane's inception was in the thick of all of them - is that both John and their customers will get cold shouldered. People who know Ariane's history will already know who I mean. People who don't may wish to look at Ariane's history, the man behind it's history and the various companies he folded without any warning or notice, without paying the developers whose products he published. Note, not company, companies. He did this several times.
I must point out that I do not know that the same thing is happening here, although I do not trust Warbirdsim in the slightest and if they do have technical problems (what, all of them at once?!) I find it very hard to believe that no-one can get to a computer and update people. The whole situation and "company" is exceptionally suspicious.