There is apparently a new Colt CR6920 variation on the market. The Colt SKU for it is: CR6920-BBBW
An organization called “Iron Valley Supply” state on their website that this carbine version is an Iron Valley Supply exclusive.
The Colt AR-15 Resource
"A site dedicated to the history of the Colt AR-15 rifles, carbines and associated items"
The Colt AR-15 Resource 