Commonly train number starting form those numbers (First Three number) belongs to
101 konkan railway ( Ratnagiri div. )
102 Konkan railway ( Karwar div. )
1 and 2 for exp and SF trains..5 for passanger . 6 and 7 for local,demu ,or memu .
What I meant to ask was which trains get no starring from 1 and which from 2
jab 1XXXX series khatam ho gya kisi zone ka wo 2XXXX use kar rhe hai.
jaise 12301 se 12398 tak sara used up hai , isleye ER & ECR 223XX use kar rhe hai.
I saw sf trains of wcr also using 221××sequence and 121×× inadvertantly.m ay be bcoz 11××× is shared by cr and wcr both.