Shazaam! Citi increase forecasts, page-13

I suggest you check your stats and read their reports.

March quarter breakeven was 57AUD. This was 52 AUD in the month of march, which is very good.

Assuming a typical 15% discount to the market rate, 48 USD a tonne goes down to 40.80, then assuming exchange rate of .8 audusd (conservative) this makes 51AUD per tonne. This at worst would be a 6AUD per tonne loss but given the CFR of 52 per tonne in the month of march, and expected cost synergies into the future, realistically 48USD is just under BCI's breakeven... a far cry from the $10 you state.

And chances are it would be better than this because if IO plunges the AUD probably will too.