The planned appeal by the four men convicted of a failed bomb plot hinges on whether the home-made explosives they were carrying were viable.
All four men claim that the plot was an elaborate hoax and that they never intended carry out a bombing.
However, the Forensic Explosives Laboratory (FEL), a top security government facility which tested the devices, concluded that they would have worked had the chemical recipe been correct.
It is this conclusion that will be called into question if the men file appeal papers.
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The Supreme Court is set to decide on whether disabled travellers are legally entitled to have priority use of wheelchair spaces on buses.
There will be some brightness, with the best of the sunshine towards the south and southeast where it will again be chilly.
It is hoped the 7,400-mile journey will become a cost-efficient and time-saving way of transporting trade between China and the UK.