Should also add that Sterling did EMA - CPH, OSL & ARN back around 2008 iirc. I did a CPH-EMA sector, I think around 2/3rd full, and I paid about £50 a couple of weeks before travel. No idea how corresponding frequencies / loads / yields would have been on OSL & ARN, but I would expect stronger demand at BHX, and an E175 would be easier to reach B.E.P. than a 735, or one of Norwegian's 738s.
I wonder if the new BER will create an opportunity for the right carrier to (re) launch a BHX service - think that needs its own thread.