Ann: Reserves Update, page-36

I'm not sure what you are referring to by this? It's just like how a Company releases financial statements for year ending 30th June 20XX in September. They need time to prepare the statements.

The reserves have been calculated based on updated modelling of the reservoir from production performance (pressure etc). They take data to 30 June and then need to crunch the numbers through algorithms.

As reserves also takes into account the economics of the gas sold (i.e. has to be sold at a profit), another part of the calculation is the price obtained. Since they will be linking up to a higher valued market via the NGP in 3 weeks, otherwise stranded gas is now considered economic and is also added to the reserves.