NR has clarified that LHB allocation is totally handled by Railway Board. So it's useless to talk to them over this :)
I don't think secondary maintenance is a big difference.
Actually, RJPB aur IPR k washing apron ka tender ek hi vendor karta hai, tender bhi ek hi hota hai jisme dono included hota hai. Isliye jab 12402 aati hai RJPB tab cleaning karne wale staff board kar jate hain Magadh me aur IPR me safai karke wapas aa jaate hain 12401 se :D