The review comes on the back of WestSide’s 2012 full-year production results, with MHA Petroleum Consultants providing new numbers.

Along with the bump in 2P reserves, its proved reserves increased more than six-fold to 47.2PJ while its 3P reserves jumped 22% to 885PJ.

WestSide chief executive Julie Beeby said the upgrade was recognition of the work it had done on increasing the estimated ultimate recovery of its wells.

“This reserves upgrade validates the effectiveness of WestSide’s operating practices and particularly our success in rejuvenating older wells to improve estimated ultimate recovery per well, which in turn has delivered a substantial uplift in Meridian’s 2P reserves,” she said in a statement to the market.

Beeby also flagged the potential for its 3P reserves to be converted to 2P reserves in the years ahead.

WestSide is still the subject of a mystery 52c per share takeover bid, with no firm offer yet put to the CSG company.

It originally received a $165 million bid from a party later revealed to be LNG Limited early last year, which was looking to secure gas supply for its Fisherman’s Landing LNG project at Gladstone.

It eventually pulled out of the running, telling the market it would prefer to set itself up as a tolling company, leaving the upstream development of resources to other companies with deeper pockets.

WestSide then announced late last year that another party had come to the table and was undertaking due diligence, with speculation rife that it could be PetroChina.

PetroChina had been in the market last year, buying up Molopo Energy’s CSG assets in Queensland for $41 million and agreeing to supply the Fisherman’s Landing development gas from Molopo’s assets.

The Chinese major’s parent company is also the parent of China Huanqiu Contracting & Engineering Corporation, which owns 19.9% of LNG Ltd.

PetroChina will also help find Chinese buyers for LNG from the project.