▁Tang ▁Y ul in , ▁and ▁Li u ▁Gu it ang ▁in ▁a ▁military ▁conference , ▁ ▁together ▁they ▁decided ▁to ▁re organ ize ▁their ▁troops ▁and ▁changed ▁their ▁name ▁to ▁the ▁ <0xE6> <0x8A> <0x97> 日 <0xE8> <0xAE> <0xA8> <0xE8> <0xB4> <0xBC> 军 ▁" Res ist ▁Japan ▁Th ief ▁P un itive ▁Ex ped ition ary ▁Army ", ▁F ang ▁Z hen w u ▁was ▁to ▁be ▁commander - in - ch ief , ▁Tang ▁Y ul in ▁deput y ▁commander - in - ch ief , ▁Li u ▁Gu it ang ▁Right ▁Route ▁commander , ▁Ji ▁Hong ch ang ▁Left ▁Route ▁commander . ▁ ▁S urr ounded ▁by ▁National ist ▁forces ▁to ▁the ▁south ▁and ▁Japanese ▁to ▁the ▁north ▁the ▁decision ▁was ▁taken ▁to ▁leave ▁from ▁D ush ik ou ▁and ▁advance ▁south ward ▁toward ▁Pe ik ing . ▁ ▁After ▁the ▁meeting , ▁Ji ' s ▁Left ▁Route ▁troops ▁pushed ▁south ward ▁via ▁the ▁He i ▁River ▁toward ▁Hu air ou ▁east ▁of ▁the ▁Great ▁Wall ▁and ▁the ▁Right ▁Route ▁troops ▁under ▁F ang ▁Z hen w u ▁moved ▁west ▁of ▁the ▁Great ▁Wall ▁along ▁the ▁B ai ▁River ▁to ▁the ▁sout heast . ▁Both ▁forces ▁crossed ▁the ▁Great ▁Wall ▁on ▁September ▁ 2 0 ▁and ▁on ▁September ▁ 2 1 , ▁Ji ▁attacked ▁Hu air ou ▁and ▁F ang ▁Z hen w u ▁attacked ▁and ▁occupied ▁Mi y un ▁on ▁the ▁same ▁day . ▁ ▁Meanwhile , ▁Li u ▁Gu it ang , ▁after ▁tal ks ▁with ▁S ung