12263/64 Pune - H. Nizamuddin AC Duronto - यह है पुणेकर वालों की राजधानी जिसका speed है सबसे Great, नहीं पहुंची है अब तक अपने लक्ष्य स्थान पर Late. - Sahil Khandare

• This starts with 305/306 HWH MKA Pass being converted into 19/20 Howrah Barauni Mithila Express in 1960 (pic 1 & pic 2)

• In 1971, another train appear numbered 21/22 North Bihar Express along with 19/20 Mithila Express both running b/w HWH-SPJ (pic 3)

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In 1995, the 19/20 appears as the Kathgodam Express (Bagh Express) and 21/22 appears as Howrah Muzaffarpur Mithila Exp. (pic 4).

• pic 5 shows a 105/106 (later 3025/3026) HWH-BJU weekly Express (later to SPJ & finally MFP) being introduced in 1984. This train also appears as 'North Bihar Express' in some cases (pic 6) & also in an unofficial TT of 1990s I am having, if u can read bengali (pic 7). This train vanishes after 1995 when the Howrah Gorakhpur Express was introduced.

It is upto u which train u are looking for & will consider as ur claimed North Bihar Express.