The short answer is: by crashing the share price management has...

The short answer is: by crashing the share price management has reduced the fair value of a deferred liability thus creating an accounting profit for the reporting period.

To prevent accounting chicanery the value of a deferred payment (the 71.5m unlisted options issued to LDA) have to be accounted for as a liability and written up (or down) according to movements in the underlying derived asset - the share price.

The value of the unlisted options that LDA hold as part of the Put Option Agreement is unknown but a fair value is calculated for accounting purposes only according to a mathematical formula that accounts for the uncertainty of predicting future events. Since the calculated fair value of a liability decreased during the reporting period the change in value has to be recognised as a profit.

If the fair value of the options swing the other way in future the change will be itemised as an expense item in the company accounts and will contribute to a loss or a reduction in profit for that reporting period.