They have previously stated what the projected production costs...

They have previously stated what the projected production costs are on more than one occasion if I remember correctly.
With the apparent rush to get the report out it may have been simply overlooked.
They did state that there was in the quarter higher outgoings due to ramping up and teething problems ect (my words)
They could have said last quarter was $25 production cost and next quarter will be $13.50 production costs + tea and coffee but that would have been a little silly to write.

I have no concerns following the old estimate until stated otherwise.
If production cost significantly rise from the estimate , it would be unwise not to report it.