I guess that tax is payable on a 'per unit' basis, so based on...

I guess that tax is payable on a 'per unit' basis, so based on volume of fish sold ?

If the net value of fish at the sea is constant each reporting period, the tax liability will be constant.

So a practical example, because tassals inventory is expected to reduce this half (inventory had reduced by 2.5tonnes in Q1 update), deferred tax will reduce by the amount of tax they actually paid on that 2.5t of finished goods.

If consumer prices go up, the amount of tax payable on that 1.5t could be more than they had previously estimated (and visa versa), those adjustments are accounted for in SGARA under AASB 141.

And the bottom line, is these adjustments are why there can be no franking credits available when a profit is made (previous estimated prices where higher than realised prices), now that prices (at least export) have increased it makes it more likely there will be franking credits accrued. (assuming similar result to last year).