I would look at it more as we have a credit on what we already have allocated, but it amounts to the same thing.
Don't take my word as gospel, but I assume your assessment is essentially correct.
i.e. cap = $80m, we currently have $70m, so $10m space.
SA had $1m of LTBE 2005 bonus not earned, so either
we now have $69m allocated on an $80m cap or as you view it, $70m on an $81m cap
Same diff.