Should the current appeal be put on hold pending further information about the Libyan the US is seeking to extradite for the bombing; this may lead to significant new evidence.
https://www.bbc.co.uk/news/world-us-canada-55337459
The problem is that Libya has next to no involvement in the bombing.
As best as we can tell the bombing was bought and paid for by Iran and perpetrated by Ahmed Jibril and his cronies.
The bomb was put onto the plane at Heathrow, by planting the samsonite case in the loading bins destined for the flight the night before.
The "official theory" is that the bomb was loaded onto an aircraft in Malta by Megrahi and the bomb was then flown via Frankfurt and interlined onto PA103. Subsequent evidence (which Rolfe is much more familiar with) disproves that scenario entirely.
The other claim is that fragments of circuit board found in the wreckage identify a timer used as part of the bomb as being Libyan in origin.
The evidence does not show that the fragments of circuit board found were part of any device that brought down the plane. The assumption is just made that hey we found this dodgy bit of circuit that comes from a timer, and the plane was blown up, so it must have been the bomb. There is no physical evidence that links the fragment of circuit to the bomb (it wasn't tested for explosives residue for example, thanks to incompetency of the original investigation team)
That's the only connection to Libya. That and the Gauci evidence that id's Megrahi as being the guy that bought the clothes found to be packed in the bomb suitcase. (which is essentially worse than worthless)
If the US have fresh evidence then great, lets evaluate it. I'd like to know why exactly it's taken them this long to make a case against someone else.
Given the extremely flimsy nature of the evidence in their previous case, and given that if you look carefully at all the evidence so far presented you cannot help but come to the conclusion that Megrahi had nothing to do with the Lockerbie bombing, I am not holding out much hope that their case against this new Libyan is going to hold water.
If new evidence does come to light and subsequently proves me wrong, I will happily hold up my hand and say so, but I am not holding my breath.
As to your question. Not the appeal should not be held up. The conviction should be overturned immediately and fresh investigations ordered to find out what actually happened and who was actually responsible.
For all of the research I have done over the years about Lockerbie I cannot tell you who blew up the plane, how they did it, or why.
I suspect it was the PFLP-GC. But I cannot show you enough evidence to prove it. The best we can do is prove that Megrahi wasn't involved.
One day I would very much like to know who was involved, though I suspect that day might never arrive.