As far as I know, Hasselblad only sells equipment one of two ways—to a reseller who then sells to the end user or thru their online store. If you order thru their online store, it has no method for backordering items that are out of stock. For instance, I just checked the
XCD 21 mm lens and it simply says "sold out" just like the H6D-100C does.
If you're looking to order one and wait for a backorder to be filled, you could order online from a reseller.
Adorama will let you add one to your cart: "On Backorder - Order now, your card will not be charged until it is ready to ship." Better yet, talk to Steve Hendrix at Capture Integration.
https://www.captureintegration.com/contact-usIf you're really in a hurry, try checking with dealers to see if they have one in stock... like
K&R Photographics. Like Steve, they're nice folks, easy to work with, and professional.
Personally, I've had to wait so many times, over the years, for backordered items due to manufacturers being out of stock that I consider it pretty common. For high-end/low-volume items in particular, I have often experienced lengthy wait times for delivery. I don't recall being given an explanation; but then, I also don't recall asking for any.
Are you actually purchasing an H6D-100C or are you conveying some
secondhand information?