I think it is if you have some significant new evidence or argument which has not been considered at trial or appeal?
So if it can be proved the Aga caused the burns this would be new evidence?
No.
https://www.cps.gov.uk/legal-guidance/appeals-court-appealHearing new evidence
The Court of Appeal may hear new evidence that was not adduced in the original proceedings (section 23(1)(c) Criminal Appeal Act 1968), if:
it appears capable of belief;
it may afford any ground for allowing the appeal;
it would have been admissible;
it is an issue which is the subject of the appeal;
there is a reasonable explanation for the failure to adduce it.
Imo the Aga burn thing doesn't appear capable of belief but lets forget that. What would be the reasonable explanation for the failure to adduce it at trial?
At trial you can pretty much throw the kitchen sink at it. Once the jury return a verdict, to say your backs up against the wall is an understatement. The grounds for appeal are narrow and focused as you can see from the above.
Even if the CCRC/CoA accepted the Aga/burns how would this overcome the silencer evidence and all the other evidence the prosecution put forward showing it wasn't SC?
I'm sorry but Bamber and his people are nits. And this extends to the solicitor.