Cika wannan jumla:
Ilinden<unk>Preobrazhenie Tashin hankali na 1903, Tatarchev ya jagoranci gwagwarmayar juyin juya hali, yayin da wakilan baƙi suka zama hukumar gudanarwa ta ƙungiyar. Don darajarsa, Tatarchev bai yi watsi da yakin neman juyin juya hali ba lokacin da aka murkushe tashin hankali. Daga baya ya zo cikin rikici tare da magoya bayan Yane Sandanski kuma bai shiga cikin ayyukan IMRO zuwa Kyustendil Congress a watan Maris na 1908, inda aka nada shi a matsayin mai ba da shawara ga Kwamitin Harkokin Waje na IMRO. Bayan Juyin Juya Halin Turkiyya ya goyi bayan Union of the Bulgarian Constitutional Clubs, amma bai shiga cikin ayyukanta ba. A cikin 1910 an zabe shi a matsayin memba na Kwamitin Tsakiya na IMRO. Lokacin da Bulgaria ta shiga Yaƙe-yaƙe na Balkan da Yaƙin Duniya na Farko, an tura Tatarchev zuwa gaba a matsayin likitan runduna. A ƙarshen yaƙe-yaƙe ya kasance ɗaya daga cikin waɗanda suka fara wakilcin wucin gadi na tsohon IMARO.