From yesterday's (24th November) Kolkata edition of The Telegraph, I could gather the undernoted information about the new 5 digit numbering system for trains. The new 5 digit number will start with
a) 1 for all Mail/Express and Superfast trains including Duronto, Jan Shatabdi, Garib Rath, Sampark Kranti, Swarnajayanti etc. Also Rajdhani and Shatabdi e.g.2837 Howrah Puri Express becomes 12837
b) 5 for all conventional passenger trains e.g. 201 Howrah Puri Passenger becomes 58001
c)...
more... 3 for all EMU locals e.g. K103 Howrah Kharagpur EMU Local becomes 38603
d) 6 for all MEMU trains e.g. 347 Kharagpur Tata MEMU Passenger becomes 68011
e) 7 for all DEMU trains e.g. 1SD Santragachi Digha DEMU Passenger becomes 78001
f) 0 for all special trains with limited run period including Ordinary/Superfast Mail/Express, conventional passenger trains, EMU/MEMU/DEMU locals etc. e.g. 1DK Digha Kharagpur DEMU Special Passenger becomes 08021, 0803 Howrah Mysore Special Express becomes 08003