explain this (in General)

how is it that since starting my ncb and retiring my main char with 400k mpr that my BA costs have gone from 563, down to 288, back up to 563 and now sitting at 736?

Something needs to be fixed.

(and my highest active char is only 18k score 15k pr)

within the first 16 hours of making my NCB, BA cost was already up to $909 (was eight-hundred some-odd with my older char). I would assume this is because BA costs are tied to your potential monetary gains, which are severely hindered below 5-10k MPR, then the receive a decent boost. and are slow to grow from there...