The convention standard is that Blue & white pair go to the middle two contacts on an RJ, the orang & white to the next outer pair. That's normally on an RJ11 or RJ12 style connector with four contacts.
However, if it is actually an RJ45 (8 contact) with four wires starting at one side, it's not connected to any standard I've seen?
Ethernet wiring using RJ45s traditionally have the middle pair a the blue & white, for dual use of fixed wiring - that pair (& brown pair) were not used prior to gigabit ethernet.