Only German sites make mention of it.
If they do arrive here in the USA, the flood of humanity through the doors of any gun stores selling them will look like rush hour on the Tokyo subway. I'll crawl over the top of other HKPRO members to get mine.
Believe me when I prophecize that a genuine SD receiver gun from Hk will be regarded someday surpassing the collectibility (and reflected market price) of a semi-auto FAMAS or SIG-550 in the case with all accessories, unfired. I just cannot imagine it happening.