They're mass released. The production run is smaller than mainstream TFs like Animated or the movie toys, but it's still a mass production. It's by no means a limited production like what HasTak do for exclusives (e.g.: conventions, e-Hobby etc.), and even then, these exclusives are typically repaints/retools of recently produced moulds.

And there have been numerous times when reissues have even shelf-warmed. A classic example was God Ginrai... I don't know about Toowoomba, but here in Sydney that toy shelfwarmed really badly at import stores. At the end prices were slashed to $20 in an effort to clear dead stock! The Micromaster gestalt reissues also moved slowly, as did some TFC reissues... I remember seeing prices of some TFC reissues being reduced to $65. And there have been reports of Encore Omega Supreme and Metroplex shelf-warming too.