Last year in February the BATF confiscated their inventory. Apparently the feds were not happy about how the serial numbers were attached/moulded to the plastic.
Click to expand the images:
From the press release:
The CAV-15 MKII receivers are back in production, after receiving approval from BATF Technology Branch for the method of affixing the serial number plate to the lower. We are currently filling back orders for our dealers and OEM clients. We will begin taking retail orders when all dealer back orders are filled. Please check with our dealers to see if they have in stock what you need.
We are currently not selling complete lowers, or complete rifles. Our vendors for these parts have substantial back orders. We currently have no ETA for these parts. If you are concerned about impending legislation, buy a lower receiver now and assemble it into a complete rifle when the supply chain stabilizes.