The Nikon D5500 and D7200 DSLR cameras have been officially listed as discontinued on the official Nikon Japan website:
Both models were announced in 2015.
It will be interesting to see what Nikon has in mind for their future APS-C line of DSLR cameras. There have not been any reliable rumors about a new APS-C based mirrorless solution.
The Nikon D5500 is currently in stock at Adorama (back ordered at B&H). The Nikon D7200 is in stock at both Adorama and B&H.