A spokesman for the LLDC board, which is tasked with sorting out the stadium's future, said:
"We have been notified that Leyton Orient have made the decision to issue proceedings for judicial review.
"Whilst this is disappointing, we believe that our processes have been robust, fair and transparent and that the challenge is misconceived."
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A teenager has been airlifted to hospital after being stabbed outside a DLR station in south-east London.
By law, the Met Police has a duty to police public land outside grounds - that's costing them £9.3m a season.
John, who began running for Age UK back in the 1980s when he was aged 53, has raised an incredible amount since then - more than £40,000.