Don't forget Y-20, which has the same priority as J-20 for PLAAF. Y-20 not only provides PLAAF with strategic air lift capability, but can also serve as platform for AWACS, fuel tanker and other special-purpose aircraft. These are the areas that PLAAF is still very weak and has a higher priority than strategic bomber.
The experience gained in developing Y-20 and various H-6 improvements can help the development of the next-generation strategic bomber. Remember China does not have much experiences in designing and developing large airframes.