I admit to knowing nothing of the mechanics - but it seems to me the
problem is how apt deals with partial files. As apt appears to know how
big the file is when it starts downloading it should be able to identify
partial downloads. A certain % of these will not allow downloads to
resume when interrupted - the majority will continue where they left off.
Maybe it could be as simple as removing so many bytes from the end of
the file before resuming?
I admit to knowing nothing of the mechanics - but it seems to me the
problem is how apt deals with partial files. As apt appears to know how
big the file is when it starts downloading it should be able to identify
partial downloads. A certain % of these will not allow downloads to
resume when interrupted - the majority will continue where they left off.
Maybe it could be as simple as removing so many bytes from the end of
the file before resuming?