Mitsubishi Ki-51 "Sonia", unidentified unit markings 九九軍偵, 分からない部隊マーク

九九軍偵の尾翼マークからどんな部隊か分かりますか？
Can you identify the units of these "Sonias" with the undocumented tail markings?

The location in the photo above, is said to be the Kanemaruhara Airfield in Tochigi Prefecture. Note that the aircraft next to the second from the left with a tail marking or fifth from the front, has the very old style canopy that opened sideways. 場所は金丸原飛行場です。

"Rising Decals" has included decals for the previous badly destroyed Ki-51 in its "Unknown and Less Known Units" set.