Originally scheduled to shut down at the end of September 2014, the reactor is now likely to continue operations for an additional 15 months, Reuters reports.
An unnamed company spokesman said, "The PSR (periodic safety review) submitted to the ONR includes a review of the safe operation of the site for the next 10 years and includes generation to the end of December 2015 of Reactor 1."
Confirming the receipt of the PSR, the ONR has also expressed its plans to respond to Magnox prior to the scheduled shutdown next year.
The PSRs are carried out every 10 years at nuclear power stations in UK to confirm that the plants are safe to operate for another decade.
The 490MW reactor started operating in 1971 adjacent to its twin reactor, Wylfa 2, which permanently shut down in April 2012, due to limited fuel stocks.
Identified to house new nuclear power installations, a site adjacent to the existing Wylfa plant was purchased by Japan’s Hitachi with plans to construct two or three 1,300-MW reactors.
