B29's were used to bomb japan from airfields in s.china.1st combat missions started in june 1944 from chengtu.Because of extreme costs of operations,these raids continued at relatively low intensity until Jan.1945.I think there were 12 raids in all.
The entire B29 effort then moved to the recently captured Marianas Islands, which were much closer to Japan.
Perhaps it is a locally produced recog model for chinese AA gunners and fighter piolts !! hope this helps, regards, Big Ned