Australian cruiser here. They are very strict about not applying for shareholder credit more than 90 days beforehand. In fact I applied at 89 days and was told it was too early and reapply in less than 90 days!
I was unaware of the policy change in regard to combinable OBCs, and so was refused SOBC as MOBC had already been applied.
The cruise was paid in full in May.
I am a bit narky that others have been able to have the credit applied waaay in the future, but because we have to wait till under 90 days to apply, it is "too bad, so sad".